The road needed to ship chemical weapons out of Syria has been seized by troops loyal to President Bashar al-Assad, as the conflict passed its 1,000th day.
The Damascus-Homs highway had been blocked for around 20 days, preventing the delivery of fuel to the capital, as troops battled with rebel fighters to secure control of the town of Nabaak.
The Syrian army has been fighting for several weeks to secure the Qalamoun region, north of Damascus, in a bid to sever rebel supply routes across the nearby border with Lebanon.
"We're hearing that the eastern part of Nabak is falling to regime forces, fighting alongside Hezbollah fighters," reported Al Jazeera's Andrew Thomas from the Lebanese capital, Beirut.
"We don't have accurate casualty numbers, but it is understood to be a heavy toll."
The Al-Watan newspaper, which has close ties with Assad's administration, quoted a military source as saying government forces had killed or captured some 100 opposition forces in the town, and seized a large weapons cache.
On Sunday, a top ranking Hezbollah commander, Ali Bazzi, was among the dead in the fight for the Qalamoun region.
We came down to the basement here to find this entire family lying dead. Each one of them received more than 50 bullets.
Women and children have also been among the dead during the fighting in Nabaak. One woman who spoke to Al Jazeera said she found several bodies in a house in the town on Sunday.
"We came down to the basement here to find this entire family lying dead," she said. "They were executed by guns. Each one of them received more than 50 bullets. There are still another five, we are sure they were also executed, but we do not know where they are."
Civilians had been trapped in the town during a two-week siege, and there was a serious lack of medical supplies, said our correspondent.
The world's chemical watchdog said on Sunday that the transportation of Syria's chemical arsenal out of the country could be delayed, due to technical difficulties.
The Organisation for the Prohibition of Chemical Weapons had previously planned to rid the country of the highest priority weapons among its stockpile by the end of the year.
"This may not be possible perhaps because of the technical issues that we have encountered," OPCW director Ahmet Uzumcu said on arrival in Oslo - where he will on Tuesday receive the Nobel Peace Prize on behalf of his organisation.
Despite the possible hold-up, Uzumcu said he was "confident that we will be able to meet the deadline of June 2014 to destroy all chemical weapons in Syria".
In total, 1,290 tonnes of chemical weapons, ingredients and precursors are to be destroyed.