At least 21 civilians including 10 children have been killed in just one evening as Russia and the Syrian regime attack civilian targets in opposition-held Idlib.

The Syrian Observatory for Human Rights, in an updated toll, said a ground-to-ground missile fired by an regime and Iranian forces that hit a makeshift camp for the displaced near Qah village close to the border with Turkey killed 15 civilians, including six children, and wounded around 40 others.

The missile crashed near a maternity facility in the camp, it said.

Internally displaced refugees were reported to be among those killed, while some of the injured were taken to Turkish hospitals across the border in Hatay.

Meanwhile footage of tents engulfed in flames circulated social media, along with dozens of wounded children being treated on hospital floors.

Syria Weekly: A small step towards the fight for justice for Assad's victims

Elsewhere, "Russian military aircraft" targeted the town of Maaret al-Numan in the south of the province, the Observatory said, and "six civilians were killed, among them four children".

A number of people were wounded in the raid, some "in a critical state", and the toll there was likely to rise, the Britain-based monitor's head Rami Abdel Rahman reported.

The northwestern Idlib region is dominated by Islamists of the Hayat Tahrir al-Sham group (HTS), formerly the Syrian affiliate of Al-Qaeda.

However the enclave has become the last-resort place of refuge for 3 million Syrians fleeing the conflict and regime brutality in other parts of the country.

Most of Idlib province remains out of the control of the Syrian regime, as do adjacent areas of Aleppo, Hama and Latakia provinces.

The Observatory has a wide network of sources on the ground and determines those responsible for such raids by the type of aircraft and weaponry used, as well as their flight plan.

Between the end of April and the end of August, Idlib was pounded ceaselessly by Syrian soldiers backed by Russian air power.

The Observatory estimates that nearly 1,000 civilians were killed in that period, and the UN says that more than 400,000 people were displaced.

Moscow announced a ceasefire at the end of August, but the Observatory says there have been sporadic attacks since then, and that dozens of civilians have been killed.

On October 22, in his first visit to the embattled northwestern region since 2011, Assad said defeating militants there was the key to ending the country's eight-year-old civil war.

The war in Syria has killed more than 370,000 people and displaced millions.

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