GARISSA, Kenya When Abdullahi slipped across the Kenya-Somali border to join the fighters of Islamist militant group al Shabaab in 2009, the livestock herder from northern Kenya found himself among recruits from around the globe.
There were ethnic Somalis who had grown up in Australia, Britain, France and the United States. But there was also a large number of fellow Kenyans in the group's ranks. They included, unexpectedly, dozens of young men who did not share his Somali ancestry or language but came instead from the green, tropical heartland of Kenya where Christianity is the dominant religion.
Abdullahi, then aged about 20, initially dismissed those men as opportunists who had pretended to convert to Islam to win work as guns for hire.
Then he saw them in battle.
"They were good fighters. I saw the way they would advise us to fight, to defend ourselves," Abdullahi said of his two years in al Shabaab, during which time he fought Somalia's weak United Nations-backed government. "I fought one battle outside Mogadishu. Half of us died... (The Kenyans) were very brave, the way they ran towards gunfire."
That's exactly what worries Kenyan and Western security agencies. Al Shabaab has been waging an insurgency against Somalia's fragile interim government since 2007 and formally became part of al Qaeda earlier this year. Abdullahi's account is part of a mounting body of evidence - including intelligence picked up by security agencies, research by the United Nations and accounts by Muslim Kenyans interviewed for this story - that suggests al Shabaab is mentoring a new and increasingly multi-ethnic generation of militants in the region.
That could have major ramifications not just for Somalia, which has been without a working government for two decades, but also for countries such as Kenya, Tanzania and Uganda, relatively stable democracies whose economies are among the steadiest in Africa. This week, Kenyan politicians blamed a bombing in central Nairobi on al Shabaab, which means "Youth" or "Boys" in Arabic.
Al Shabaab seeks to impose a strict version of Sharia or Islamic law. The group emerged as a force in 2006 as part of a movement that pushed U.S.-backed warlords out of Somalia's capital, Mogadishu. It remains Somalia's most powerful non-government armed group and in its propaganda, promotes the idea that many Muslims are flocking to its cause around Africa.
Washington and London have long worried the Somali group aimed to expand its influence in Africa. That suspicion was confirmed last July when a United Nations investigation found al Shabaab had created extensive funding, recruiting and training networks in Kenya.
Much remains unclear about the strength of the group's following outside Somalia. Some academics, including Kenya-based independent researcher Paul Goldsmith and University of California scholar Jeremy Prestholdt, urge caution because Kenya's Western allies may play up the significance of the group to justify budgets and expanded surveillance powers.
Abdullahi's story about his time in al Shabaab couldn't be independently verified. His account is consistent with those of other young Kenyan men involved in Islamist radicalism, including another former al Shabaab fighter interviewed for this story, 22-year-old Mohamud, and by clerics, police officials, diplomats, security officials, lawyers, academics and social workers.
The flow of recruits continues, they say.
A skinny, bearded figure in sandals, dusty black trousers and a sports shirt, Abdullahi lives in Mandera, a few hours drive from Garissa, the town in Kenya's dusty north where he spoke with Reuters. He quit al Shabaab last year, he said, because he grew disillusioned with the violence and with promises of payments that never came. Back home, he is unemployed and hopes to study at university. His militant days are behind him, though he asked that his full name not be used because he worried about official reprisals.
Pinning down the number of non-Somalis who have joined al Shabaab is difficult. Boniface Mwaniki, head of Kenya's Anti-Terrorist Police Unit, said it was impossible to compile accurate figures because the Kenyan-Somali border is porous and long.
In separate interviews, a Western private security consultant, a European diplomat, a lawyer familiar with the militant Islamist community in Kenya, a community organizer and an independent researcher with an international non-governmental organization all said that up to 600 non-Somali Kenyans are currently fighting with al Shabaab, around 10 percent of the group's total troops.
The militant group is also using its connections and social media to inspire the creation of loose networks of sympathizers in Kenya, Tanzania and Uganda. Kenya's Security Minister George Saitoti worries that this support could allow al Shabaab to threaten East Africa, and especially Kenya, the region's economic hub.
Non-Somali East Africans have taken part in al Qaeda attacks before, including the 1998 bombings of the U.S. embassies in Kenya and Tanzania and the suicide bomb attack on an Israeli-owned hotel near Mombasa in 2002. A few have risen high in al Qaeda: Indian Ocean islander Fazul Harun Mohamed once worked as Osama bin Laden's private secretary in Afghanistan.
Concern has risen since a coordinated bomb attack on Uganda's capital Kampala in July 2010, which killed 79 people watching the soccer World Cup final. Al Shabaab claimed responsibility, saying the attacks were retribution for Uganda's troop deployments in Mogadishu as African Union peacekeepers.
In September last year Kampala's High Court jailed two Ugandans on charges connected to the attack.
"We've seen a very different dynamic now. The young converts are the ones who are being lured into terrorism," said Al-Amin Kimathi, a Kenyan human rights activist who was released last year after being held on suspicion of involvement in the Kampala bombings.
Concern over al Shabaab's growing East African contingent was one of the motives for Kenya's decision to send troops into Somalia last October.
ELDERS LOSE CONTROL
The pull of militancy is placing new strains on the region's Muslim communities, say elders, clerics and younger Muslims.
"The older generation has lost control of the youngsters. They've lost it completely," said Kimathi, who was born a Christian in Nyeri in Kenya's central highlands and converted to Islam in his mid-30s.
Most converts, he said, are "overzealous" and easy targets for al Shabaab's recruitment campaigns, especially if they are poor. Because the young men, often converts, do not fit the conventional profile of an Arab or Somali militant, they are harder to track, one European diplomat said.
But Kenya's police have made life harder for the group's recruiters. Back in April 2009, when Abdullahi joined al Shabaab, it was possible for recruiters to carry out indoctrination sessions in a mosque. Abdullahi met al Shabaab clerics from Somalia when they came to preach in his home town of Mandera.
"It was after afternoon prayers. We went to a corner of the mosque where we could talk quietly," he said. "They said that jihad was going on in Somalia and that we were all brothers and should join the jihad. They promised us money and food."
"They said Islam was under attack, and they mentioned Ethiopia. They told us the Ethiopians and other Christians were attacking Islam and they wanted to wash Islam out of the country. That made me feel so angry."
Fuelled by that anger and the fact he could not make enough to feed his family, he headed across the border. Abdullahi had been a herder and then worked for an aid organization, distributing rice and water.
"I joined for the jihad, I wanted to defend Islam. But of course we needed money to support the family," he said.
The Somali clerics who had visited his mosque paid him $1,000 and said more money would follow. It did not.
"Of course I believed in jihad," Abdullahi said, shaking his head. "But what I found them fighting was not jihad."
"YOU WANT TO ATTACK"
Al Shabaab may have lost Abdullahi, but there are others ready to take his place, many of them not ethnic Somalis. In the port city of Mombasa on Kenya's Indian Ocean Coast, sermons by fiery clerics stoke anti-Western sentiment.
Suleiman Adam, a 25-year-old mobile-phone card salesman, says his radicalization began in 2002 when he enrolled in an Islamic boarding school north of the city. Adam, whose forefathers came from Sudan, is the son of a truck driver who could not afford to send his son to a regular high school.
Looking back, Adam said, it was obvious that some of his teachers at the school sympathized with al Shabaab.
There were moments when he agreed. "If you see some American tourist, like a kaffir (unbeliever), you just feel like you want to attack him. You are of that mind that ‘These people are bad. These people want to finish this religion of Islam.' That was what was in my mind ... You feel like going and exploding yourself."
But even in his radical days Adam was not as extreme as some of his classmates, who included non-Somali Kenyans like him. "There are some... who are 50-50. We felt it's not a jihad, going to explode yourself, that's not a jihad. It wasn't making sense. But there were those who were 100 percent. They believed in that."
That faith is exploited by unscrupulous radical preachers, say community leaders like Imam Mustafa Bakari. Sitting in a cafe opposite his Masjid Fathi mosque in Mombasa, he said he worried that the recruitment would continue "because preachers in Mombasa are continuing with these wrong teachings.
"We have Muslims here who want to go to Somalia to join al Shabaab, but I've told them they should not go to Somalia because the war there is not jihad. In Somalia it's Muslims fighting Muslims and that is not jihad."
A sense of piety is often fuelled by more practical considerations. Mwalimu Rama, 38, a former youth leader who now works for a non-governmental organization that counsels young Mombasa radicals, has friends with al Shabaab in Somalia. Some occasionally call him to chat about their exploits, he said.
But when he tries to persuade them to come home, they scoff. "What, you have a job for me? You want to employ me? Is there actually anything good there, if I come back?" he said they ask.
THE SALAFI INFLUENCE
Financial considerations also play in Kenya's capital Nairobi. It's not hard to find al Shabaab sympathizers in the Eastleigh district, which teems with ethnic Somalis. But over the past few years the group's influence has extended to other areas, including Majengo, a huddle of streets beside the downtown area.
One of the most vocal of its support bases is a group called the Muslim Youth Centre, once headed by radical preacher Ahmed Iman Ali, who now lives in Somalia. Iman Ali used to preach at the Masjid Sunna, a small Majengo mosque, where he would openly praise al Shabaab, residents say.
The mosque's current imam, Alzadin Muriuki Omar, 27, a thin, sprightly figure in shirt and trousers, denied that Masjid Sunna had any ongoing connection to al Shabaab. He said he has told his congregation not to fight in Somalia, arguing that God commands his followers to solve disputes through discussion.
Kenyan media reports that the mosque is the centre of terrorism in East Africa are wrong, Omar said, as a hen clucked about his feet in the mosque's yard.
Omar and many of his congregation are Salafis, followers of an ultra-conservative brand of Islam that has its roots in Saudi Arabia.
Salafis are in the minority among Kenya's 4.3 million Muslims, but are beginning to flex their muscles. Older, non-Salafi Muslims in Majengo view Omar's congregation with suspicion, in part because Omar's followers have recently asserted control over the district's main mosque, the Pumwani Riyadh, one of Nairobi's oldest.
Imam Yahya Hussein, deputy imam of Pumwani, insists his followers will retake control of the mosque once current renovations are finished.
Sitting in a white plastic chair in a temporary mosque made of wooden poles and sheets of blue plastic and green canvas, Hussein suggested the spread of Salafi Islam in Majengo was a result of the increasing influence of Somalis with longer exposure to Salafist thinking. While many Salafis are no less revolted by al Qaeda-style violence than other Muslims, their puritanical branch of the religion is espoused by many of the militants behind al Shabaab.
"We have been against the Somali influence in this area for as long as I can remember," Hussein said. "As the population of the Somalis started growing in Nairobi ... the Somalis came here day time and night time," he said. "They have money. So it's the influence of money. So the youth here will tell the old men, ‘What are you giving me? You are not giving me anything,'" he said. "Where there is money, people will go."
It doesn't help that the police response to radicalism is often heavy-handed and corrupt, community activists say. Diplomats say that poor Muslim coastal areas of East Africa such as Mombasa or Tanzania's Zanzibar islands are particularly vulnerable.
It's "not far-fetched at all" to suggest that political stability on the East Africa coast could be threatened, a Western official said.
Stig Jarle Hansen, associate professor at the Department of International Environment and Development Studies at the Norwegian University of Life Sciences, reckons that in terms of the quality of their response, "the Kenyans are where countries like Norway and Britain were about 20 years ago. They are using hard power, not soft power. They are not going into the communities to talk. They are going in to arrest. Engagement is not happening and that's not just because of a policy weakness but also because of the poverty of the state. They have less resources."
Police spokesman Eric Kiraithe said the force was not heavy-handed and such an allegation was "mischievous."
Kimathi, the Kenyan human-rights activist, also blames counter-terrorist activities by Western and African forces. He spent almost a year in detention, much of it in solitary confinement, on suspicion of involvement in the Kampala bombings. He had visited Uganda to advise several Kenyans transferred there by Kenyan authorities after they had been picked up for the attacks. The prosecutor dropped murder and terrorism charges against him in September 2011 and released him.
The Ugandan prosecutor declined comment on his decision.
Despite his experience, Kimathi says there is a problem with the expansion of al Shabaab into non-Somali ethnic groups in East Africa.
"That is what is worrying now," he said. "They are still finding their ways around ... They think the whole world is their theatre."
(William Maclean reported from Nairobi and Mombasa, Noor Khamis from Nairobi, Mohamed Ahmed from Garissa; Additional reporting by David Clarke, Richard Lough, James Macharia, Humphrey Malalo and George Obulutsa in Nairobi; Writing by William Maclean; Editing by Simon Robinson and Sara Ledwith)