There were four separate attacks at York University last week, according to police.

A 20-year-old woman was sexually assaulted Friday just before 5 p.m. She was attacked shortly after exiting a TTC bus at the school’s Keele campus.

Three hours later, another student was approached by two men who asked if they could buy drugs. When the victim responded with “no,” one of the men allegedly picked up a metal pipe and smashed it over the student’s head. York says the student was taken to hospital.

Two students were robbed at knife point earlier in the week.

There have been about a dozen reported attacks at York since the start of the school year.

The university posts security alerts on its website and emails students after an attack has occurred. According to the website, the university plans to boost its security.

Toronto police say no arrests have been made.

Anyone with information is asked to call 416-808-2222.