Reports of Sudanese air force and militia massing in West Darfur and renewed bombardment of villages indicate another wave of violence is imminent, the UN has warned.
According to aid workers, Sudanese government aircraft bombarded areas near Abu Sarraw barely two weeks after attacks on the towns of Sirba and Abu Surouj displaced thousands of civilians.
The latest aerial bombardment targeted villages at the base of opposition-controlled Jebel Moun areas.
"I am very concerned for the civilian population caught in the middle of this violence," John Holmes, UN Under-Secretary-General for Humanitarian Affairs and Emergency Relief Coordinator, warned in a statement on 18 February.
"Should further attacks occur, the consequences for 20,000 civilians in this area could be disastrous," he added, calling on parties to the West Darfur conflict to refrain from further attacks and exercise maximum restraint.
The renewed violence, according to the UN Office for the Coordination of Humanitarian Affairs (OCHA), follows earlier fighting between the Khalil Ibrahim faction of the Justice and Equality Movement (JEM) and government forces north of the West Darfur capital, El Geneina.
An estimated 160,000 civilians were affected, including those currently at risk in Jebel Moun. "The civilian population has experienced widespread displacement, property damage, and significant trauma and loss of life," OCHA noted. "Approximately 57,000 civilians were displaced due to the offensive."
At least 2.4 million people have been displaced by violence in Darfur, of whom 300,000 fled violence in 2007.
"All parties have to act now to stop these attacks and help bring those responsible for attacks against civilians to account under international law," Holmes said.
The 8 February attack killed one national staff member of the International Committee of the Red Cross (ICRC), and left thousands of civilians displaced and seeking shelter in neighbouring Chad.
Aid workers said Abu Sorouj and Sirba, about 55km north of El Geneina, were razed to the ground. The two towns had hosted at least 40,000 displaced civilians who fled insecurity in surrounding villages in 2004.
The Sudanese government denied targeting civilians, saying the attacks were intended to dislodge JEM fighters who were hiding among civilians. JEM fighters in plain clothes, hundreds of Kalashnikov guns and heavy weapons were collected, it said. JEM denied the claims.
Conflict in the Darfur region of western Sudan started in 2003 when communities there launched a rebellion against the Khartoum government, accusing it of marginalising them. The government responded by arming militias to counter the rebellion.