With the help of US airstrikes, fighters claimed to have secured more than 90 percent of the city so far, and are now attacking the ISIS group's last remaining positions in the coastal city, Reuters reports.
Sirte has seen intense fighting in the last few months between government forces and ISIS fighters, who gained a foothold in the country following the power struggle and security vacuum left in the wake of the downfall of Moammar Gadhafi's regime in 2011.
The Libyan forces, mostly from the adjacent city of Misrata, support a United Nations-brokered government based in Tripoli.
Efforts to bring unity to the deeply divided North African country were dealt a major blow last month when the Tobruk parliament voted "no confidence" in the UN-backed government based in the capital, Tripoli.
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