KHARTOUM (Reuters) - More than 20 people were killed when south Sudan's army attacked renegade militia fighters Monday, forcing them to abandon one of their bases, the military said.
South Sudan's army has started a new offensive against forces loyal to rebel leader George Athor hiding out in the south's Jonglei oil state, a diplomatic source told Reuters on Monday.
The region has been hit by a wave of mass killings in the past month, casting a shadow over preparations for the independence of the south, due to take place on July 9.
Just short of 99 percent of southern voters chose independence in a January referendum, promised in a 2005 peace accord that ended decades of civil war with the north.
The civil war, fought over oil, ideology and religion also saw fighting between rival southern militias.
Analysts say there are fears the region's bitter divisions may be re-emerging. Southern leaders have regularly accused Khartoum of backing Athor and other militias to destabilize the region ahead of its split, an accusation dismissed by Khartoum.
"He (Athor) was planning another attack. So the SPLA (the southern army) launched a pre-emptive attack on three places," said SPLA spokesman Philip Aguer.
Aguer said 14 of Athor's men and seven southern soldiers were killed in one attack and he was still waiting for details from the other two. He added Athor's men were forced to abandon one base in Korwac.
Athor, speaking over satellite phone, told Reuters 176 southern soldiers died in the fighting and he lost just 19 men. He said he had been forced out of one base. There was no independent confirmation of any of the figures.
The former senior officer in south Sudan's army rebelled last year after saying he was cheated out of the governorship of Jonglei in national elections.
Athor said he was keen to negotiate a settlement with the southern army but "they keep attacking us. In their mind they want to crush us. But I don't think a guerrilla force can be crushed."
The southern army accused Athor of breaking an earlier ceasefire by massacring more than 200 people in the Fangak area of Jonglei mid February.
French oil group Total leads a consortium controlling a largely unexplored oil concession in Jonglei.
(Reporting by Andrew Heavens; Editing by Matthew Jones)