NAIROBI - Dozens of people have died in northern Kenya in a week of fierce clashes between rival ethnic groups, aid sources and reports said on Saturday.

The ongoing unrest, centred around the town of Moyale in Marsabit county on the frontier with Ethiopia, has seen villages burned down and many families forced to flee over the border.

According to the Standard newspaper, at least 27 people have been killed and thousands more displaced over the past week.

Kenyan peace and anti-tribalism campaigner Jaffer Isaak said he believed the toll was somewhere between 70 and 120 dead, while an independent international aid source, who asked not to be identified, said "many dozens" had been killed.

Switzerland&39;s ambassador to Kenya, Jacques Pitteloud, said he was rallying other European envoys to join an effort to convene peace talks between the rival communities.

"People are dying, people are being pushed over the border, villages burned, houses looted. It has to stop before it degenerates further, so it&39;s important to start peace efforts," Pitteloud said.

The conflict pits the majority Borana community, which has traditionally dominated the area since Kenya&39;s independence 50 years ago, against the Rendille, Gabra and Burji communities, who are allied in a grouping called the ReGaBu and have now emerged as a dominant political force.

Clashes between rival cattle herding pastoralists in the region are common, with herders often carrying guns to protect their animals, but the recent fighting has been unusually heavy.

Kenya&39;s government on Friday ordered the army be deployed in the area.

Isaak, who heads Pillar of Hope, an anti-tribalism group, said Marsabit county was "on fire" and accused security forces of doing nothing to stop the fighting -- and even being supportive of the Borana militia, which supports Kenya&39;s ruling coalition.

"People are slaughtering each other. The situation is out of control. The police are just watching, doing nothing. The army are just watching," he said, adding that the main highway linking Kenya and Ethiopia had been blocked.

The Standard newspaper also reported that heavy fighting was continuing in Moyale on Saturday, with plumes of smoke visible over the town, and fierce gunfire heard and military helicopters flying overhead.