Extra police, security and attendants are working at SkyTrain stations in the Metro Vancouver area after RCMP detonated a bomb found on the elevated tracks.
Transit Police spokeswoman Anne Drennan says about a dozen detectives will also be out Saturday as they investigate how the explosive device ended up on the tracks between two stations in Surrey.
She says a passenger on the train spotted three canisters strapped together with tape on Friday afternoon and alerted authorities.
Drennan says the canisters that were the size of fire extinguishers could have been thrown onto the guideway or it's possible someone climbed up to the area.
She says explosives technicians believe the object would not have detonated on its own but may have been electronically or manually set off.
The incident disrupted service on the SkyTrain system between the Scott Road and Gateway stations for about three hours.