St. Michael’s College School says it informed police of an allegation of serious sexual assault of a student on its grounds on Wednesday, two days after administrators were first made aware a video was circulating of the incident.

In a statement released to parents Friday, the school’s administrators built a week-long timeline of what they say occurred and start by saying they were first shown a video on Monday of an incident that occurred in a boys’ washroom.

The school does not specify what occurred in that video, but the school says the encounter “severely violates” the school’s code of conduct.

The school said it started an internal investigation into the first incident on Monday and notified police about it.

Police have previously confirmed they were contacted by the school on Monday about an incident separate from the one that an investigation was eventually launched into. Police spokesperson Meaghan Gray said “advice was provided to the school and no further action was taken or received” with regards to the reported incident.

The school says it expelled four students in connection with the washroom incident on Tuesday.

In the timeline issued by the school on Friday, it acknowledges administration received a second video, believed to show the alleged sexual assault of a male student with an object in a locker room, sometime on Monday.

The school says that through Tuesday and Wednesday, it continued its own investigation into the first incident in the washroom and the second incident involving the alleged sexual assault. The school said it interviewed all students involved and their parents.

School officials said on Wednesday they conducted interviews with students and notified “families involved that police will be contacted by the school” in connection with the second incident.

According to the school, student was suspended in connection to the “washroom” incident and four students were expelled in connection with the “locker room” incident.

“Upon completion of its internal investigation, School Administration provides information related to the second incident to police, and gives the second video (locker room) to police,” the school noted in its timeline.

On the same day, Wednesday, media outlets including CP24, began contacting the school and police about the second incident involving an alleged sexual assault with an object.

Police had previously said they were first notified of this video by media.

Administrators say they also held an assembly at the school that day to update all students, except ninth-graders (most of whom would have been off campus for ‘Take Our Kids to Work’ events), and informed them to “delete related videos in their possession”, as per police directive.

Toronto police also released a public advisory on the same night, saying the video of the alleged sexual assault constitutes child pornography.

“As school administrators and educators, we bear a heavy responsibility to help guide our students through a challenging period in their lives - when external forces are often in conflict with the notion of doing the right thing - and these incidents were a stark reminder that we have more work to do,” the school’s administrators said in their Friday statement.

On Thursday, the school says it received a threat and called in police to safeguard the campus.

Administrators went to each homeroom class to provide support and held an assembly to update grade 9 students.

The school says it was also made aware of “a third incident” on Thursday and notified police about it.

Police spokesperson Meaghan Grey confirmed to CP24 that officers are investigating a third incident, but did not provide any details. They describe them as "a number of occurrences involving incidents of alleged assaultive and sexually assaultive behaviour.

They say they believe there are other witnesses who have not yet come forward.

Anyone with information is asked to call police at 416-808-2922.

Also on Thursday, administrators and football coaches met with parents and members of the school’s junior football team.

The school says it now has crisis counsellors and private security guards on campus. Two meetings between parents and school administrators were planned for Friday afternoon and evening.

The order of the Basilian Fathers of North America, who founded the school, said Friday they are “deeply saddened and troubled by the events that have come to light over the past days.”