Police are searching for a suspect who allegedly forced a woman to the ground and sexually assaulted her near a GO bus terminal in Newmarket early Friday morning.

According to police, the 18-year-old victim was walking westbound on a pathway that runs parallel to Davis Drive from the station at around 3 a.m. when she was approached by a man who grabbed her, forced her to the ground and then sexually assaulted her.

The attack was subsequently broken up by another man who came upon the scene and spoke with the victim, but left the area before police arrived on scene.

Police say the woman sustained minor injuries in the assault and was taken to hospital.

The suspect is described as 30 to 40 years old, about five-foot-nine with a lean build and some sort of covering obscuring his face.

Police are appealing to anyone with information to come forward.

Police are also asking the man who interrupted the attack to contact them.

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