Nine people, including six children, have been killed in a government air strike on a rebel stronghold in Syria, a monitoring group said on Saturday.

The Syrian Observatory for Human Rights (SOHR) said the nine had been harvesting olives in northwestern Idlib province’s mountainous Jabal al-Zawiya region.

Others were left wounded, some in serious condition, added SOHR.

Most of Syria has been recaptured by Syrian President Bashar al-Assad since the beginning of the civil war in 2011, which has left more than 500,000 people dead and millions displaced.

Parts of the north are controlled by the Kurdish-led People’s Protection Units (YPG), while Idlib province remains in rebel hands.

Hay’at Tahrir al-Sham (HTS), led by al-Qaeda’s former Syria branch, controls swathes of Idlib province as well as parts of the neighbouring Aleppo, Hama and Latakia provinces.