UPDATE 6-Fire guts Kenya's main airport, chokes regional gateway
* Busiest airport in east Africa closed after fire
* Arrivals building devastated, flights diverted
* No casualties reported
By Drazen Jorgic
NAIROBI, Aug 7 (Reuters) - A fire engulfed Kenya's main airport on Wednesday, forcing the suspension of international passenger flights and choking a vital travel gateway to east Africa.
The country's anti-terror police boss said he did not believe that there was a terror link to the fire even though it coincided with the 15th anniversary of a twin attack by Islamist militants on the United States embassy in Nairobi and Dar es Salaam, the commercial capital of neighbouring Tanzania.
Authorities said they will on Thursday begin preparing the airport's domestic terminal, which escaped the blaze, for handling international flights, using tents to create extra space. Domestic flights had resumed by Wednesday evening, and outward-bound cargo flights were due to resume hours later.
The raging blaze engulfed the terminal buildings and lit up the early morning sky, sending billowing clouds of black smoke rising in a plume that was visible from miles away.
The intense heat repeatedly drove back firefighters who battled for five hours to put out the fire, the worst on record at Jomo Kenyatta International Airport, east Africa's busiest.
Boniface Mwaniki, head of the anti-terror police unit, said there was no connection with "terrorism".
"We don't want to speculate, but at this stage we do not think there is any such link," he told Reuters. "Even if we are commemorating the 15th anniversary of the bomb blasts, we don't think it is terrorism."
Nevertheless, authorities had beefed up security at the airport and key installations in east Africa's biggest economy.
Security analysts said there was no indication of any link to Islamists that Kenyan soldiers are battling in neighbouring Somalia as part of an African Union force.
"It doesn't bear the hallmarks of an al Shabaab operation but one never knows," said a regional security analyst, speaking on condition of anonymity.
There were no immediate reports of casualties from the fire, which started in the arrivals and immigration area.
The blaze stranded thousands of passengers at the airport and exporters of perishable produce, mainly flowers, feared for their export-driven business, a leading source of foreign currency earnings for Kenya alongside tea exports and tourism.
The fire was also a blow to Kenya right at the start of the peak tourism season, a key sector for the Kenyan economy.
"This is disastrous," Jane Ngige, chief executive officer of exporters association Kenya Flower Council, told Reuters.
Mahmud Jan Mohamed, the managing director of Kenyan hotel operator TPS Serena, said "the last thing we need is this", but added that it was still a little early to tell the full impact of the disruption to tourism.
Business travellers and tourists were diverted to other airports, mainly to the port city of Mombasa.
Shares in Kenya Airways, which uses the airport as its hub, fell as much as 2 percent, before recovering.
The airline said its overnight flights from London and Bangkok would land as scheduled in Nairobi on Thursday morning, the first overseas flights at the airport since the fire.
TENTS FOR INCOMING TRAVELLERS
Preparations to handle more international flights would be carried out on Thursday at the airport's domestic terminal, said Michael Kamau, cabinet secretary for transport.
"From tomorrow we will be preparing this unit ... as an international terminal for departures and arrivals," Kamau told reporters. "We started pitching tents on the airside for handling departing passengers."
Foreign carriers using the terminal include Emirates , British Airways, Qatar, KLM ), Turkish Airways, South African Airways and Ethiopian airlines.
The airport, built in 1978 with a capacity for 2.5 million passengers a year, handles 6 million or about 16,000 a day.
Inside the gutted building, neat lines of metal trolleys with melted plastic handles were the only clear reminder that the building - whose roof partially collapsed - was once an airport terminal.
Some travellers searched for their luggage amid the charred ruins while staff from Western embassies waved their national flags to attract passengers looking for a place to stay.
"We are now here illegally since we don't have a visa and therefore can't leave the airport," said Juan Cabrera, a French United Nations worker travelling to Zanzibar from Burundi with his wife and baby.
"I'm just wondering how I get back home or continue our trip. No one seems to know."
Some tourists to the world famous Masai Mara Game Reserve where the annual wildebeest migration is taking place were stranded and had cancelled their bookings, tour operators said.
Passengers faced bus trips of hundreds of miles to reach the Kenyan capital.
"I am taking them to Nairobi form here. They are many, even the five buses that were deployed to do this job will not be enough," Samuel Mwangi, one of the bus drivers in Mombasa said.