WARNING: The video at the top of this story contains footage that some may find disturbing.

The Special Investigations Unit is investigating the death of a man who went into medical distress at Barrie’s police station on Friday afternoon.

According to the SIU, a 32-year-old man was arrested by Barrie police around 2:30 p.m. Friday and brought to the station at Sperling Drive.

During the booking process the man went into medicial distress and paramedics were called in to assist, the SIU said.

He was taken to Royal Victoria Regional Health Centre where he was pronounced dead a short time later.

In a press release, Barrie police said it notified the SIU which has invoked its mandate. As a result,  Barrie police will not provide any further information.

Police did not release the man's name and would not say what charges he was facing.

Family and friends have identified him as Olando Brown.

Bystanders took cellphone video of the arrest which has since being posted on social media.

The SIU has assigned five investigators to probe the incident. They have designated three Barrie police officers as subjects of the investigation and one other as a witness.

The Special Investigations Unit is called to probe any interaction between an Ontario police officer and a member of the public that results in death, serious injury or an allegation of sexual assault.