Forces aligned with Libya's unity government said they had made significant gains in residential districts of Sirte on Tuesday as they battle to oust Islamic State from its coastal stronghold.

Rida Issa, a spokesman for the government-backed brigades, said they were securing the "700" neighbourhood, just south of central Sirte, and had also made ground to the west of the city centre. Sixteen brigade members had been killed and 60 wounded in Tuesday's fighting, Issa said.
Brigades composed mainly of fighters from the western city of Misrata launched a campaign against Islamic State a month ago, advancing rapidly towards Sirte from the west.
In the past week they had faced counter-attacks from militants holed up inside the city, who have deployed snipers, mines and car bombs to try to force the brigades back.
"Our forces are combing the 700 neighbourhood after fierce clashes," Issa said on Tuesday. "The electricity company headquarters, TV and radio building, Number 2 neighbourhood, and Bin Hamel mosque are all recaptured."
Government-backed forces had also seized a second ammunition store from Islamic State, he said.
The U.N.-backed Government of National Accord (GNA) has been trying to unite Libya's factions since arriving in Tripoli in March, and has created several operations rooms in an effort to coordinate the campaign against Islamic State in Sirte.
A separate GNA-aligned force that controls some of Libya's key oil terminals has forced Islamic State back to the east of Sirte, recapturing several villages from the jihadist group.
Islamic State expanded into Libya from 2014, establishing a presence in several towns and cities. It took full control of Sirte last year, benefiting from a security vacuum and from the political chaos that has roiled Libya since long-time leader Muammar Gaddafi was toppled in an uprising in 2011.