BEIRUT: Two waves of air strikes on a jihadist-held town in northwestern Syria have killed at least 13 civilians over the past 24 hours, a monitoring group said on Saturday, reports AFP.

Four children were among the dead in the early morning strikes on the Idlib province town of Khan Sheikhun on Friday and Saturday, the Syrian Observatory for Human Rights said.

Observatory chief Rami Abdel Rahman said the strikes were probably carried out by the Syrian air force, which has been carrying out an intensifying bombing campaign against jihadist targets in Idlib province alongside aircraft from ally Russia.

Like most of the rest of Idlib province, Khan Sheikhun is controlled by Hayat Tahrir al-Sham, an alliance of jihadist factions dominated by Al-Qaeda's former Syria affiliate.

The town hit the headlines in April when it was the target of a sarin gas attack that killed at least 87 people, 30 of them children.