A teenage boy has been killed and several others injured in a mini-bus crash south-east of Adelaide.

Police believe the group was returning from a camp when the vehicle, carrying 12 teenagers, rolled on the Dukes Highway near Ki Ki on Friday.

An ambulance spokesman said one of the teenagers was dead when help arrived.

Another teenager had been airlifted to the Flinders Medical Centre suffering significant neck and shoulder injuries.

Five others were taken by ambulance to nearby hospitals. The other teens suffered only minor injuries.

The crash temporarily closed the Dukes Highway, the main road link between South Australia and Victoria.