Rebels from the Sudanese region of Darfur have carried out an attack outside the region, on a town about 200km (125 miles) from Khartoum.
Government aircraft have been sent to Hamrat al-Sheikh, where fighting is continuing, the army says. A local official said 12 people had died.
The raid was carried out by rebel groups which did not sign a peace deal.
Governor of North Kordofan state Faisal Hassan Ibrahim said that eight policemen, two security men and two women were killed in the fighting in Hamrat al-Sheikh, during which several public buildings were destroyed, reports the AFP news agency.
The rebels attacked the town with 50 trucks armed with heavy weapons, he said.
After refusing to sign the accord in May, rebels from the Justice and Equality Movement, (Jem) and breakaway factions of the Sudan Liberation Army formed an alliance.
The US accuses the government of backing Arab militias against the region's black African residents.
The government denies backing the Janjaweed militias and blames the violence on the rebels, who took up arms, accusing the authorities of ignoring the region.
The unrest in Darfur has also spread to neighbouring Chad, which has a similar ethnic make-up.
Chad's government accuses Khartoum of backing its rebels and says it has repulsed an attack on the border town of Ade.
PHOTO CAPTION
A rebel of the Justice and Equality Movement (JEM) is seen in the northern part of the Darfur region in July 2004. (AFP)
BBC