At least four peacekeepers have been killed and 15 others wounded when their convoy hit a mine in northern Mali, a spokesman for the UN has said.

Olivier Salgado, a spokesperson for UN peacekeeping mission in Mali, said on Tuesday that the group of Chadian soldiers were returning to the town of Kidal when they struck a mine.

The deaths took place about 30 km north of Kidal, which is home to a separatist Tuareg rebel movement.

Al-Qaeda and other armed
 groups are also active in the area. 

UN troops are now trying to stabilize the north, and peace talks have begun between the Malian government and Tuaregs, who maintain a heavy presence in Kidal and have pushed back against the authority of the Bamako-based government.

Al-Qaeda is not participating in those discussions. 

"A peace process is under way, some want to compromise it, that's totally unacceptable and irresponsible,'' Bert Koenders, the UN special envoy for Mali, said.

Northern Mali has experienced a series of attacks on UN peacekeepers in recent weeks but Tuesday's attack was the largest in months.  

Including those who died on Tuesday, 15 peacekeepers have been killed in Mali this year.

Source: Agencies