Seven children were killed in southern Syria's Daraa province on Saturday when an "explosive device" detonated, state media reported.

"Seven children" were killed "and two other people were injured, one of them a woman, when an explosive device planted by terrorists" went off in the city of Sanamayn, state news agency SANA reported, quoting a police source.

The Syrian Observatory for Human Rights war monitor gave a different toll, saying that "eight children of different ages were killed and another was wounded" in the blast.

The Britain-based monitor said militias were accused of planting the device to target an unidentified person in the area.

Daraa was the cradle of the 2011 uprising against President Bashar al-Assad's rule but it was returned to government control in 2018 under a ceasefire deal backed by Russia.

The province has since been plagued by killings, clashes, and dire living conditions.

Syria's war, which escalated into a deadly conflict that pulled in jihadists and foreign armies, has killed more than 507,000 people, displaced millions, and battered the country's infrastructure and industry.