Switzerland coach crash kills 28, including 22 children
The wreckage of the bus Police described the crash as "unprecedented"
At least 28 people - including 22 children - have been killed in a bus crash in Switzerland, police say.
Another 24 children were injured in the accident in the canton of Valais, near the border with Italy.
The bus - which was carrying children from Belgium - crashed into the wall of a tunnel. Both drivers were killed.
The children from the Belgian villages of Lommel and Heverlee were returning home after a skiing holiday. There were 52 people on the bus.
The bus hit the wall of the tunnel near the town of Sierre on Tuesday night.
Two classes of schoolchildren from the Flemish-speaking part of Belgium were travelling home after spending a skiing week in Val d'Anniviers, in the Swiss Alps.
In Brussels, the Belgian foreign ministry said most of the children were aged around 12, and the bus was one of three hired by a Christian group, the AFP news agency reports.
Some of the injured were later flown by helicopters to hospitals in Lausanne, Berne and other Swiss cities.
Swiss journalist Ruth Seeholzer told the BBC that some 300 rescuers were working at the scene of the crash.
She said that the two-lane tunnel was not busy with traffic when the accident happened and driving conditions were normal.
Police described the crash as "unprecedented".
An investigation is now under way.
A helpline for families has been set up, and many parents are expected to arrive in Switzerland shortly.