Islamic State of Iraq in the Levant (ISIL) fighters drove Syrian government forces from the western town of Maheen on Sunday, a monitoring group reported, as fighting escalated despite a flurry of diplomatic activity and talks between regional rivals.
In a fierce assault that began with the detonation of two suicide car bombs, ISIL militants took from government forces the town of Maheen in the southwest of Homs province, the Britain-based Syrian Observatory for Human Rights reported.
Some 50 fighters on the government side were killed or wounded, and clashes raged afterward on the outskirts of Sadad, a mostly Christian town nearby, the group said.
ISIL issued a statement claiming the advance, which brought it within 13 miles of the north-south highway linking Damascus to Syria's other main cities — Homs, Hama and Aleppo. Syrian state media made no mention of the attack.
The Observatory's Rami Abdulrahman said the attack might have been in response to pressures that ISIL is under elsewhere.
ISIL is separately fighting both the Syrian army and rebels in western Syria and has launched several attacks on government-held areas since Damascus launched a new offensive against it east of Aleppo, backed by Russian air strikes.
On the other side of Syria in the northeastern province of Hasaka, ISIL is facing a new offensive launched by a recently formed U.S.-backed rebel alliance.
The Observatory reported fierce fighting between the rebel alliance, which includes the Kurdish YPG militia, and ISIL fighters in the area of al-Houl near the Iraqi border.
Syrian parties to the multisided conflict said they see no end to fighting between rebels and the government despite talks in Vienna on Friday that included Iran for the first time. Iran's supreme leader meanwhile said elections should be held to end the war, echoing a proposal by Russia that has been dismissed by President Bashar al-Assad's opponents as a ruse by his allies to keep him in power.
It all underlines the intractable state of the four-year-long war that has killed 250,000 people and driven more than half the population from their homes, causing a refugee crisis in neighboring states and Europe.
Talks between world powers in Vienna on Friday adjourned with calls for a nationwide ceasefire but key differences remained between rivals backing opposing sides.
The war has entered an even more violent phase in the month since Russia began air strikes in support of Assad. Differences over his future remain the main obstacle in the way of diplomatic efforts.
While the United States and Russia back rival sides in the war between the government and rebels in western Syria, both are also waging separate campaigns against the ISIL group that controls wide areas of the east and the north.
The United States says it will step up its fight against ISIL in Syria and Iraq, having decided to station special forces in Syria to support rebels fighting ISIL, and to position more U.S. jets in Turkey and expand air strikes.
Air strikes by Turkish and U.S. aircraft in Syria on Saturday killed more than 50 ISIL fighters, Turkey's state-run Anadolu Agency said on Sunday.