A female middle-school student is missing after a boat carrying 21 students capsized Saturday on a river in the north-central province of Quang Binh, online newspaper Dan Tri reported.

The accident occurred on the confluence of Nan and Son rivers in Quang Trach District at around 6:15 p.m. Twenty-one students of Quang Minh Commune Secondary School were on a small boat to get to a local church for Christmas celebrations.

When the boat was around 50 meters away from shore, it capsized due to swift-flowing waters.

Nearby residents used boats to rescue 20 students, nine of whom fell unconscious from water shock.

Nguyen Thi Lai, a seventh grader, is still missing.

The students were not accompanied by adults, police said, adding the boat was only capable of carrying five people.