(Adds latest killings, paragraph 11)
By Abdi Sheikh
MOGADISHU, June 26 (Reuters) - Conflict in Somalia has killed 2,136 civilians so far this year, bringing the death toll since an Islamist-led insurgency began in early 2007 to 8,636, a local human rights group said on Thursday.
The Mogadishu-based Elman Peace and Human Rights Organisation said it had also recorded 11,790 civilian injuries since the start of last year, when rebels began attacking the Somali government and its Ethiopian military allies.
"If the international community does not intervene to stop the massacre in the country, Somalis will soon become extinct," the group's chairman, Sudan Ali Ahmed, told Reuters.
As well as civilian deaths, hundreds of fighters on both sides have also died, locals say.
The insurgency -- the latest in a cycle of conflict since the 1991 fall of a military dictator -- has compounded the effects of drought and poverty to create what aid workers call one of the worst humanitarian crises in the world.
"Somalia is no longer on the verge of catastrophe, the disaster is happening now," Medecins Sans Frontieres (MSF) director of operations Bruno Jochum told a Nairobi press conference in the latest international warning.
The United Nations says one million Somalis -- out of a total population of about nine million -- are living as internal refugees in the Horn of Africa nation.
But the Elman rights group, in figures given to Reuters, put that number at 1.9 million. Tens of thousands of Somalis have also fled to neighbouring Ethiopia and Kenya.
The governments of Ethiopia and Somalia dispute the numbers of dead and displaced, saying rights groups are accepting Islamist "propaganda" and exaggerating the situation.
Mogadishu, the epicentre of the conflict, has seen an upsurge in fighting since a U.N.-brokered peace agreement at the start of this month. Hardline Islamists rejected the pact, signed by the Somali government and some opposition members.
In the latest violence on Thursday, Islamists killed nine policemen in Mogadishu after tricking them into a meeting, and shot dead two government soldiers in a central village, Rebay, locals and authorities said.
"More weapons from unknown sources are pouring into the country and there is no hope of life unless the political rivals reach lasting peace," rights campaigner Ahmed said.
"The death toll and the number of internally displaced persons are increasing day after day."
MSF said attacks on aid workers had risen in Somalia, as the humanitarian situation quickly worsened.
Jochum said malnutrition rates had soared since March.
"We are also facing increasing attacks on humanitarian workers which have forced MSF, and other organisations, to withdraw international staff in the last few months and weeks."
In the last three months, admissions to MSF clinics have quadrupled and are now doubling on a weekly basis, he said.
"Last week alone, over 500 severely malnourished children were admitted to our nutritional programmes," Jochum said.
Invoking the Geneva Convention on refugees, Kenneth Lavelle, MSF head of mission in Somalia, called for neighbours to open their borders.
"The Somali population are trapped in their country," he told Reuters. "They have no choice. They have to stay there and suffer ... they've got no escape."
Although the Kenyan border is officially closed, the United Nations says 4,000 Somalis a month cross the long and porous border. (Additional reporting by Hereward Holland in Nairobi; Writing by Andrew Cawthorne; Editing by Caroline Drees) (For full Reuters Africa coverage and to have your say on the top issues, visit: africa.reuters.com/) (firstname.lastname@example.org; +254 20 222 4717)