Updated

A union official says workers used air horns to scare away a black bear who appeared at an oil sands work site but they were unable to prevent him from dragging away a female employee and killing her.

Unifor spokesman Scott Doherty said Thursday seven people were working in a group area when the attack occurred on Wednesday.

The 36-year-old Suncor employee was an instrument technician, who was doing electrical work at a job site near Fort McMurray, Alberta, Doherty said.

Barrie Harrison, a spokesman with Alberta Occupational Health and Safety, says the woman was mauled by a mature male black bear that has been put down by police.

Black bears are common in Alberta at this time of year when they come out of hibernation and look for food.