Thirty-six pro-government troops were killed in a district of Syria’s capital as ISIL fighters took control in a surprise attack overnight, a monitor said on Tuesday.
“ISIL took full control of Qadam, and 36 government troops and loyalist fighters have been killed,” said the Syrian Observatory for Human Rights, which could not provide casualty figures for the extremist group.
There was no immediate comment from the government.
Observatory chief Rami Abdel Rahman said that dozens more of Syrian President Bashar Al Assad’s forces were wounded or captured, or are missing in action.
He said that ISIL launched the attack from positions it holds in the adjacent Hajar Al Aswad district.
"Regime forces are bringing reinforcements to the area around Qadam to try to retake it," Mr Abdel Rahman told AFP.
Qadam lies in a southern part of Damascus and has for several years hosted a range of Islamist rebels and extremists, including ISIL and its arch-enemy, Al Qaeda's former Syrian branch Hayat Tahrir Al Sham.
The Syrian government has used military pressure and negotiated settlements to try to clear the area.
Last week, hundreds of Hayat Tahrir Al Sham fighters left the district under a deal with the Assad regime that granted them and their family members safe passage, with most heading north-west to Idlib province.
ISIL fighters have agreed to leave the district in the past.
The extremist group put out a statement late on Monday saying it had captured most of Qadam, including areas "surrendered" to regime forces by Hayat Tahrir Al Sham.
The district is smaller than and not connected to Eastern Ghouta.