MAARET AL-NUMAN (Syria) • Syrian regime forces have seized dozens of towns and villages in north-west Syria from militants following days of violent clashes, fuelling an exodus of civilians, a war monitor said.

The fresh advances in Idlib came as Russian warplanes continued to pummel the province's south, killing nine civilians who were trying to escape the flashpoint on Sunday, the Britain-based Syrian Observatory for Human Rights said.

The ground assault by regime loyalists brings them closer to capturing one of the largest urban centres in Syria's last major opposition bastion.

"This push is an attempt to get closer to Maaret al-Numan," Observatory head Rami Abdul Rahman told Agence France-Presse (AFP).

Residents of the southern Idlib town flooded out of the area, fearing further advances, an AFP correspondent there said.

According to the Observatory, more than 30,000 people had fled the flashpoint in southern Idlib in recent days. More than 40 civilians were reportedly killed in the region in the past week.

Mr Abu Akram, a resident, said rescue workers and local relief groups were struggling to get families out.

"Everybody is working at full capacity but they can't handle such a large number of people," the father of five told AFP after he could not find a vehicle to drive his family farther north.

The militant-dominated Idlib region hosts some three million people, including many displaced by years of violence in other parts of Syria.

The Damascus regime has repeatedly vowed to take back the area and bombardment has continued despite a ceasefire announced in August, claiming the lives of more than 290 civilians and hundreds of fighters from both sides.

The United Nations has called for "immediate de-escalation" and warned of further mass displacement if the violence continues.

Syria's war has killed over 370,000 people and displaced millions since beginning in 2011 with the brutal repression of anti-government protests.

Meanwhile, the Observatory said yesterday that air raids in Syria the previous night, blamed on Israel, killed at least three foreign pro-regime fighters south of the war-torn country's capital.

The war monitor said that Sunday night's attack hit Syrian regime and Iranian positions south of Damascus.

Syrian state news agency Sana said Syrian air defences fired on "hostile missiles" coming from "the Occupied Territories", referring to Israel.

AGENCE FRANCE-PRESSE