Libyan forces prepare to detonate and dispose of explosives and shells left behind by Islamic State militants in Sirte following a battle, in Misrata Libya, September 9, 2016. REUTERS/Stringer

TRIPOLI (Reuters) - Libyan forces allied with the U.N.-backed government on Sunday battled Islamic State militants in their last hideouts in the city of Sirte, in a renewed push after a break in fighting for the Muslim celebrations of Eid.

At least two were killed in clashes after self-government forces shelled neighborhoods inside the city, targeting militants who have been holding on in a last section of Sirte after months of street-to-street fighting.

U.S. air strikes and helicopter raids along with small teams of Western special forces have helped the Libyan troops advance in Sirte and losing the city would be a major blow for the militant group depriving it of its North African stronghold.

“Our forces targeted on Sunday hideouts of Daesh in Neighbourhood No.3’s 600 block area and Geza Bahriya with heavy artillery shelling,” said Mohamed Ghasri, a spokesman for the forces, said using an Arabic term for militants.

Akram Gliwan, a spokesman for Misrata central hospital, told Reuters two fighters had been killed and six more were wounded and were brought to the hospital.

Mostly from Misrata city, 230 km (145 miles) to the north west, the government-allied forces say some commanders from Islamic State and fighters may have escaped and fled south or to the Tunisia border before Sirte was encircled.

But Ghasri said two Islamic State commanders, Hassan Karami and Walid Ferjani, had been killed in fighting inside the city, without giving details. Misrata commanders have said in the past Karami had been killed, but they have not indicated whether any body had been positively identified with DNA.

Western governments are supporting the U.N.-backed government in Tripoli as the best option to bring together Libya’s rival armed factions to stabilize the country, end Islamist State threats and stop illegal migrant smugglers.

But it has faced opposition from hardliners, especially in the east, where Gen. Khalifa Haftar has been carrying out his own campaign against militants in Benghazi. Haftar’s forces a week ago took control of major oil ports.