At least eight civilians were killed on Wednesday in a rocket attack by Syrian government forces on a school in Idlib, the country’s last opposition stronghold of Idlib.
The victims included four children and two women, the White Helmets civil defence agency reported.
The school was packed with students and teachers at the time, the group added.
The attack took place in the rebel-held town of Sarmeen in Syria’s northwest province of Idlib, said war monitor the Syrian Observatory for Human Rights (SOHR).
At least 16 others were injured in the attack, part of a months-long government offensive in Idlib, the Britain-based watchdog added.
An AFP correspondent in Sarmeen saw the remains of a missile, which was several metres long, fuming in a nearby olive grove.
The attack was part of a continuing offensive which has seen Syrian troops capture more than 40 villages and hamlets in Idlib over the past two weeks.
In late April, the Syrian government and allied Russians launched a large-scale campaign against rebels in Idlib.
In recent weeks, the offensive has intensified, forcing thousands to flee for safer areas.
According to the UN Office for the Coordination of Humanitarian Affairs (OCHA), more than 235,000 people were displaced between December 12 and 25 due to the violence.
The civil war in Syria has killed more than 370,000 people since it started in 2011 with the brutal repression of anti-government protests.
In total, 11,215 people – including more than 1,000 children – were killed in 2019, the least deadly year on record since the beginning of the conflict.