Sixteen army recruits have been injured in an accident involving armoured vehicles in canton Jura. Six of the soldiers suffered serious injuries.
An army spokesman said the four vehicles involved were travelling one behind the other at a military base in Bure on Tuesday when for unknown reasons they collided.
The police said all available ambulances in the canton were sent to the scene and the Swiss Air Rescue Service (Rega) transported the badly injured to hospital by helicopter.
The military justice has begun an investigation into the cause of the crash.
There have been a series of accidents involving the Swiss army in recent months and years.
A military vehicle tipped over while travelling on the A1 motorway last July, injuring the driver and three passengers.
A year ago, 11 people were injured in an accident in Cham, canton Zug, involving an army bus. After colliding with a car, the bus rolled over. Most of the injured were high-ranking officers from abroad who were in Switzerland to attend a Nato conference.
The army received a lot of bad press following the death of five soldiers in a rafting accident in the Bernese Oberland in 2008, and six recruits were killed by an avalanche while attempting to climb the Jungfrau mountain a year earlier.
swissinfo.ch and agencies