The United Nations said on Friday it was investigating reports of serious human rights abuses, including the execution of civilians, in northern Mali following clashes this week between northern Tuareg separatist rebels and pro-government militia.
UN-brokered peace efforts in Mali's north are in danger of unraveling because of repeated violations of a ceasefire between the Tuareg-led Coordination of Movements of Azawad (CMA) and the pro-government factions around the flashpoint northern town of Menaka.
The clashes on Thursday killed at least six civilians, including a Malian aid worker, rebels and a local source said.
The UN mission in Mali said on Friday it had sent a team of investigators to verify reports of serious abuses and the execution of civilians, possibly including an aid worker in Tin-Hamma, in Gao region.
"These abuses followed as a result of the clashes on May 20 between members of the Platform (pro-government militia) and the Coordination of Movements of Azawad," the mission said.
The National Movement for the Liberation of Azawad, a member of the CMA coalition, said in a statement that nine people including two who worked for international aid agencies were arrested by pro-government militia and executed. It added that several others were missing.
"The execution took place in public, at the town's cattle market and the bodies were still exposed in the public square as of 1500 GMT (11.00 a.m. EDT)," MNLA said in the statement, listing the names of the nine.
The Malian government rejected accusations that its troops were involved in the abuses. It said in a statement late on Friday that Malian soldiers had intervened in Tin-Hamma to drive out insurgents who had killed three civilians in the attack.
"The government is surprised by the allegations of abuses on the population attributed to the armed forces following the events in Tin-Hamma," it said. "The government rejects such accusations."
The UN mission said it was concerned about an alarming escalation of fighting in several areas of northern Mali, which was in violation of the ceasefire and could jeopardize the peace deal.
Separately, it said 12 rockets hit its camp in Ber, about 50 km (30 miles) east of Timbuktu, on Friday. It did not name the attackers but said there were no casualties.
There was a lull on Thursday. On Friday morning, sources within the rebel CMA and later videos that Reuters obtained showed fighting had resumed around the town of Menaka, which the rebels had been trying to take back since last month when pro-government forces kicked them out.
In a separate battle, the rebels also seized the town of Tessit near Gao.
Violence has continued in northern Mali despite a 2013 French-led intervention that pushed back al Qaeda-linked fighters who hijacked the Tuareg-led rebellion and seized two-thirds of the country in 2012.
A ceasefire deal was signed between the government, its allies and northern separatist groups last year, but violations of the agreement have increased since pro-government fighters seized Menaka late last month.