Toronto police are trying to identify a man they say sprayed two TTC passengers with an unknown substance earlier this week.

According to investigators, at around 5:45 p.m. on Jan. 4, a man approached a passenger at Greenwood Station and sprayed them in the face with an unknown substance.

Police say the man then proceeded to do the same thing to a passenger on the bus platform at Finch Station a short time later.

Both assaults, police say, were carried out without any provocation.

Investigators have now released security camera images of the suspect and are asking anyone who sees the man not to approach him but to call 911 immediately.