Libya’s U.N.-backed unity government condemned an attack staged by a recently formed militia group on eastern military forces close to key oil facilities, as clashes resumed on Sunday. Fighting had erupted south of the coastal town of Ajdabiya on Saturday between military units loyal to Libya’s eastern government and a group calling itself the Benghazi Defense Forces. Three people were reportedly killed and 10 wounded, military spokesman Akram Bu Haliqa said.

The Benghazi Defense Forces is mostly joind by fighters pushed back earlier this year by brigades loyal to the eastern government commander Khalifa Haftar. Haftar has been waging a campaign for two years in Benghazi against extremists, including some loyal to ISIS, and other opponents.

The condemnation by the U.N.-backed Government of National Accord (GNA) is significant because some in the east suspect the GNA – whose leadership has itself been divided – of siding with ISIS-inspired militias.

Clashes near Ajdabiya, close to three oil terminals and north of major oil fields, risks opening a new front in the conflict between forces that backed competing governments set up in Tripoli and the east in 2014.

Since March, the GNA has been seeking to replace the rival parliaments and governments and integrate armed groups, including forces loyal to Haftar, into national security forces. Nevertheless, the eastern parliament has withheld from backing the new government.

“The Presidential Council (of the GNA) strongly condemns this criminal act and holds the leaders and members of these militias fully responsible,” said a statement published on the Presidential Council’s Facebook page on Sunday.

“These militias are attacking to assist the remnants of ISIS in Benghazi and Ajdabiya which have faded and had their strength sapped by the strikes by our brave military.”

Armed groups in Libya have remained highly fragmented in the political mayhem that followed the toppling of Muammar Gaddafi in 2011. ISIS established a presence in several parts of the country from 2014, and has been active between Benghazi and the terrorist group’s coastal stronghold of Sirte, about 380 km to the west.

However, in recent weeks, ISIS terrorists retreated into the heart of Sirte after GNA-aligned forces advanced from the western city of Misrata.