Passengers exited the affected train at Patterson station Friday evening. (CBC)

One person was treated for minor injuries Friday night after someone released what might have been pepper spray on a SkyTrain in Vancouver

The incident occurred on an eastbound train just before 6 p.m. PT after it left Joyce station.

One woman told CBC News that about 40 people on the train started coughing, choking and covering their faces as some substance appeared to have been released into the air.

The passengers got off at the Patterson station and the injured person was treated at the scene.

Transit Police are investigating the incident.