BEIRUT (AP) -- Syrian government troops advanced on rebel-held areas in the country's southwestern region amid intense clashes Saturday, state media and opposition activists said, in a widening offensive that has shattered a U.S.-backed truce.
Syrian State news agency SANA reported fierce clashes in al-Lujat area, a rocky region in the eastern countryside of Daraa. It said troops advancing from the adjacent Sweida province seized two villages, adding that the rebels responded by shelling government-held areas.
The Britain-based Syrian Observatory for Human Rights also reported the government advances, saying they were accompanied by intense shelling and airstrikes. The Observatory said the escalation on the fifth day of the fighting left eight government troops dead, and 20 others wounded. Russia, the main backer of the Syrian government, said five Syrian soldiers were killed. Since Tuesday, at least 18 civilians and 10 rebel fighters have been killed, the Observatory said.
Washington warned the offensive in the region bordering Jordan and Israeli-occupied Golan Heights risks widening the conflict. It called on Russia to restrain its ally and warned of the repercussions of the fighting but didn't elaborate on how it intends to salvage the truce in place for nearly a year.
The de-escalation zone was negotiated by Russia, Washington and Jordan and has maintained calm in the strategic area since. But in recent weeks, the deal appeared to be unravelling as both the Syrian government and Israel turned to military means to achieve their goals. Damascus is seeking to build on the momentum of its successive military victories elsewhere and has turned its troops and elite forces toward the southwest. Israel, fearing the expansion of the influence of Iran and its allied militia fighting alongside the Syrian government in the area, has carried out airstrikes there against suspected Iranian targets.
Russia has been in talks to reach a settlement in the area, building on the July deal. But the talks have stalled as the fighting escalates. On Saturday, Moscow, which has come under criticism from the U.S. for the teetering agreement, blamed al-Qaida-linked militants for targeting and killing government troops. The Russian defense ministry said about 1,000 fighters attacked the government army tank division in Daraa.
The majority of the rebels in southwestern Syria are backed by the U.S. and Jordan. A minority among them who are mostly local fighters are al-Qaida-linked.
Local media activist Abu Mahmoud al-Hourani said the clashes Saturday were an escalation in a widening offensive, but denied that the rebels lost any territory. Government advances from the northeastern part of Daraa could isolate some of the rebels in al-Lajat area, cutting them off from the south.
"It is an extensive military campaign. Today there was a substantial escalation as ground battles started," al-Hourani said. "It seems they want to storm the area and to take control. But the clashes are ongoing."
Separately, Iraq's air force carried out an airstrike in eastern Syria targeting a meeting of Islamic State militants, killing 45 of them, including at least eight senior members of the group. In a statement, the Iraqi military command said the airstrike Saturday hit the meeting in Hajin, one of the last strongholds of the militants in eastern Syria. Iraq's government has been collaborating with the U.S.-led coalition and the Syrian government separately to fight the remnants of IS in Syria along the border with Iraq.
The senior level IS members killed in the strike were only identified by their posts. The Iraqi command said among the targets were the group's war minister, the head of IS's police, a senior media operative and the messenger of the group's leader, Abu Bakr al-Baghdadi. There were no further details.