Students at a high school in Rocky Mountain House, Alta., are mourning the loss of a classmate in an accident Monday.

Tanner Mayer, 15, was killed when a warning device known as a bear banger went off in a truck.

Friends say Tanner was in a parked truck when a friend found the device on the floor of the vehicle and tried to lock it. Instead, it discharged and the projectile struck and fatally injured the teen.

Grief counsellors were called in to help students at Tanner's high school. Many students have signed one of his favourite T-shirts and plan on framing it to give to the family.

RCMP are continuing to investigate. No decision has been made on charges. 

Bear bangers are readily available for sale in Canada and are often used by campers and people who work in the bush. They are pen-like devices that set off a flare.

"The device is a noisemaker, and it's designed to be fired straight up into the air," said Doug Dea, general manager of Camper's Village in Edmonton. "It reaches a height of about 30 metres, and it lets off a loud crack, [a] banging sound, and that frightens away bears."

The screw-on flare cartridge and the pen launcher are meant to be carried separately, Dea said.

In the 17 years Camper's Village has sold bear bangers, staff have never heard of any customers who had accidents using the device.