A helicopter crashed in the middle of a residential neighbourhood in Cranbrook, B.C., on Tuesday, killing four people, witnesses say. (CBC)

B.C. Hydro has suspended the use of helicopters following a fatal crash in Cranbrook Tuesday, according to a company spokesperson.

The utility may also launch its own investigation into the crash, said Susan Danard.

"In the interim, we have suspended use of all helicopters except for emergency situations because that's just a precautionary thing, but if need be, we'll certainly go further than that," she said.

B.C. Hydro had previously used Bighorn Helicopter Inc., the helicopter charter service that supplied Tuesday's flight, and Danard said the flight was routine.

A B.C. Hydro truck sits outside Bighorn Helicopter Inc.'s building after a helicopter crashed Tuesday afternoon, killing four people, including two B.C. Hydro employees. (CBC)

"Apparently, they were going off to … inspect transmission lines by helicopter and they were just beginning their patrol … when this accident occurred."

Four people were killed when the chopper crashed into a busy residential neighbourhood Tuesday afternoon.

Three people in the helicopter, including two B.C. Hydro employees, and a pedestrian all died at the scene.

The families of the two B.C. Hydro employees are still being notified, Danard told CBC News.

There is no indication how long the employees had been with the company.

The cause of the crash has not yet been determined. A spokesperson for the Transportation Safety Board said three accident investigators are expected to arrive on the scene Tuesday evening.