BEIRUT, Lebanon (AFP) — Syrian government forces were locked in heavy fighting around the central city of Hama on Thursday, trying to halt an advance of Islamist-led rebels, a war monitor said.

By late Wednesday, the Syrian Observatory for Human Rights said rebel fighters had “surrounded Hama city from three sides.”

“Violent clashes took place during the night between the rebels and the regime forces,” particularly in the Jabal Zayn al-Abidin area, just north of Hama, said the Britain-based monitor.

The head of the Observatory, Rami Abdel Rahman, said government troops were engaged in “fierce resistance and trying to stop the rebels’ advance.”

Hama is strategically crucial for the army, serving as a buffer to protect the capital Damascus.

The clashes follow a swift offensive by Islamist-led rebels who, in just days, seized significant territory, including Syria’s second city, Aleppo, from President Bashar al-Assad’s control.

Syrian state media quoted a military source late Wednesday as saying Russian and Syrian air forces, alongside artillery units, had conducted “concentrated strikes on the... terrorists” in the Hama area.

The Observatory says 704 people, mostly combatants but also 110 civilians, have been killed in Syria since the violence erupted last week.

It marks the most intense fighting since 2020 in a country ravaged by civil war broke out in 2011 but had been mostly dormant for several years.