Sudan ? Pro-government militiamen launched new attacks in Sudan’s volatile Darfur region that may have killed at least a dozen people, international observers said Sunday.

A coalition of Darfur rebel groups known as the National Redemption Front said some 300 janjaweed militiamen on camels and horseback raided the West Darfur town of Sirba on Saturday, backed by 18 military vehicles.

“The attack resulted in 32 dead, 18 injured, including women and children,” the NRF said in a statement. The rebels said janjaweed militias and elements from the regular Sudanese army burned about 100 houses and looted hundreds of heads of cattle.

A U.N. official in Darfur said the janjaweed had looted several villages and a refugee camp in the past few days, reportedly killing about 12 people. The official spoke on condition of anonymity because of the sensitivity of the issue.

African Union peacekeepers in Darfur said they were investigating the reports of fresh janjaweed raids near Sirba.