BEIRUT — The Syrian army and its allies reached Deir al-Zor on Tuesday in a sudden advance following months of steady progress east across the desert. On Thursday, the army advanced against militants in a pocket they still hold further west, pro-Damascus media reported.

Syrian state media reported an aid convoy arrived at Deir al-Zor in eastern Syria on Thursday, bringing supplies to soldiers and civilians days after the Syrian army broke a three-year ISIS siege.

State TV broadcast footage of scores of residents cheering with relief in Deir al-Zor as the convoy arrived.

The United Nations estimated that 93,000 civilians living under ISIS siege in Deir al-Zor had been in “extremely difficult” conditions, being supplied only by air drops.

The 40 trucks that reached the area on Thursday carried basic needs such as fuel, food and medical supplies to civilians, and included two mobile clinics, state news agency SANA reported.

ISIS mortar fire on neighborhoods still surrounded near the air base killed at least seven civilians and wounded dozens more on Thursday, a British-based monitoring group said.

On Thursday, the army also advanced against ISIS militants in countryside east of the city of Hama, Hezbollah’s media outlet reported.

The advance, which saw forces recapture two villages there, is part of efforts to drive the militants out of an isolated pocket of territory they control east of Hama and Homs.

Separately, the U.S. special envoy to the U.S.-led coalition against ISIS, Brett McGurk, said on Wednesday that a convoy of ISIS fighters and families from the Syria-Lebanon border was still in open desert.

The coalition is using air strikes to block the convoy from reaching ISIS-held territory in eastern Syria, to which the Syrian army and its ally Hezbollah were escorting it as part of a truce following fighting on the Syria-Lebanon border.

ISIS is fighting separate offensives by both the Syrian army and its allies in eastern and central Syria, as well as the U.S.-backed Syrian Democratic Forces in Raqqa.

The group has lost nearly half of its territory across both Iraq and Syria, but still has 6,000-8,000 fighters left in Syria, the United States-led coalition has said.