Metro Vancouver's Transit Police have released photos of three men who allegedly sexually harassed and threatened two women on SkyTrain, before attacking a Good Samaritan who tried to intervene.

On June 9 at approximately 11:20 p.m., three men boarded an eastbound SkyTrain at Sperling Station in Burnaby and allegedly started calling out to a female passenger that they were going to follow her home.

This suspect is described as a white male, early 20s, 5’9” tall, medium to heavy build, short brown hair, short beard and moustache, wearing a blue NFL jersey with the name 'Johnson' and the number '81' on the front, and wearing dark jeans. (Transit Police)

One of the men then sat down beside a different woman and allegedly made jokes to his two friends about raping her.

Another male passenger — called a Good Samaritan by Transit Police — intervened, telling the three men to leave the women alone.

The third suspect, on the left, is described as a white male, 20 years old, 5’9” tall, heavy build, short brown hair, wearing a grey hoodie with red hood and sleeves, black shorts and grey skate shoes. (Transit Police)

The Good Samaritan was then himself allegedly verbally assaulted and threatened by the three men, and followed off the train at Lougheed Station where he was punched in the face and body.

The attackers then re-boarded the train, while the victim boarded a different car, held the door open and pushed the emergency strip.

One of the suspects went after the Good Samaritan, allegedly assaulting him for a second time. All three attackers then ran off.

The victim was treated in hospital for a bleeding nose and sore arm and later released.

Transit Police spokeswoman Anne Drennan said, "While we would not suggest anyone put themselves in harm's way, we commend the victim in this incident for taking the action he did in trying to protect this woman."

Anyone with any information on the three suspects or who may have witnessed the incident and not already spoken to police is asked to contact them at 604-515-8300 or text at 87 77 77.