Airstrikes hit a school in Syria killing at least 14 children and three adults

At least 17 people are dead after an airstrike outside a school in Syria, activists said.

Most of the casualties are children as the air strikes hit as they gathered outside a school in the rebel-held province of Idlib, local reports said.

There are fears the death toll could rise further as some of the wounded are in critical condition, the group said.

The Britain-based Syrian Observatory for Human Rights put the death toll at 22, including 14 children.

Idlib is the main Syrian opposition stronghold, though radical groups also have a large presence there.

It has been regularly hit by Syrian and Russian war planes as well as the US-led coalition targeting Islamic State militants.