Khartoum - The UN-AU peacekeeping mission in Sudan's Darfur said on Sunday it is "deeply concerned" about an surge in fighting between government forces and rebels in the conflict-hit western region.
The Unamid mission said it was "deeply concerned about ongoing fighting between government forces and armed movements in the Jebel Marra area, central Darfur," near one of its bases in the town of Nertiti.
"Unamid personnel in Nertiti also reported five bombs being dropped on an area northeast of their location. The impact of the bombs was felt at the team site," it said in a statement.
Businesses in the town of Nertiti have shut down for fear of attacks, the mission said.
It gave no further details of the fighting and the Sudanese military did not immediately comment.
There have been relatively few clashes between Darfuri rebels and troops in recent months, but the mountainous Jebel Marra area in central Darfur is where much of the fighting took place last year.
Jebel Marra is seen as a stronghold for groups that rebelled against President Omar al-Bashir in the western region in 2003, complaining their region was being marginalised by his regime.
In response to the rebellion, Bashir launched a campaign to crush the insurgents using ground troops, warplanes and allied militia.
The International Criminal Court indicted Bashir over alleged war crimes in the region, and the UN says more than 300 000 people have been killed in the conflict.
There are also around 2.5 million people displaced by the fighting in Darfur, according to the UN.
Unamid peacekeepers deployed to the region in 2007 to protect civilians and secure aid deliveries.