Syrian government forces kept up their shelling of the town of Yabroud and the surrounding Qalamoun region over the weekend, as both sides claimed advances ahead of an expected all-out assault on the rebel-held town. The Britain-based Syrian Observatory for Human Rights said Sunday that government artillery targeted the outskirts of Yabroud, while clashes continued pitting regime troops and paramilitary forces against rebel militias, including the Al Qaeda affiliate the Nusra Front, as well as the Al Qaeda splinter group the Islamic State of Iraq and Greater Syria (ISIS).

The Observatory said that the rebels managed to disable a number of regime vehicles while ISIS militants were able to seize mortars and rockets during the offensive.

Lebanon’s Al Manar television, affiliated with Hezbollah, said that regime forces had managed to disrupt the rebels’ supply lines leading into Lebanon, and the Bekaa Valley town of Arsal.

Its correspondent, reporting from the region, said that the Syrian Army had the entirety of the Yabroud region in the sights of its artillery, and either severed the supply lines or could fire at will on any rebel movements seeking to use the routes.

Poor weather conditions Saturday, according to activists, slowed the regime’s offensive against the region. Activists have also disputed claims that Yabroud is the “final” rebel-held town in Qalamoun, saying that rebels retain a presence over half a dozen villages in the area. Several thousand people are believed to have fled Yabroud as the onslaught picks up pace. The Observatory said that an undetermined number of people seeking to flee Yabroud were detained at a regime checkpoint.

The Observatory said that barrel bombs continued to rain down on various parts of the country, as Aleppo-based activists said that at least a dozen fell on the northern city Sunday. Five people were killed by one of the crude devices, which landed on the neighborhood of Masaken Hanano, while the Observatory put the casualty figure at four.

Regime troops seized the nearby village of Sheikh Najjar, with casualties on both sides of the clashes, the Observatory said. Regime troops and rebels also clashed in several locations in the Old City of Aleppo, while rebels managed to block a road leading from the city’s historic citadel, the Observatory said.

Regime helicopters dropped barrel bombs on the town of Atareb in Aleppo wounding an unspecified number of people. The same devices were used to target the Damascus suburb of Daraya but the barrel bomb failed to explode. Separate barrel bomb strikes were also reported on the town of Khan al-Shih, located on the road between Damascus and Qunaitra.

Several locations in rural Idlib were targeted by barrel bombs, but only material damage resulted from the strikes, the Observatory said.

Regime forces also clashed with rebels at several locations in and around the southern city of Deraa and the suburb of Adra, near Damascus, killing at least one rebel.

On the Bab Al Hawa border crossing with Turkey, an Islamist militia clashed with members of the Janabira tribe, the Observatory said. The fighting killed two rebels and wounded at least five civilians, while also leading to the closure of the crossing.

In rural Hassakeh further east, the Kurdish PYD militia seized the village of Jazaa after clashes with ISIS, the Nusra Front and Islamist militias, which suffered “confirmed” casualties, the Observatory said.

Elsewhere, however, ISIS fighters continued to clash with other rebel groups, including Nusra and members of the Islamic Front alliance.

In other clashes between ISIS and rebel groups in rural Idlib, an ISIS commander was killed, the Observatory added.

The Observatory put Saturday’s nationwide death toll at 194 people, of whom 145 were fighters from the various sides.