TORONTO -- The family of a man who committed suicide while he was supposed to be under close medical observation has filed a multimillion-dollar lawsuit against the hospital where he died.

The family of Prashant Tiwari says the 20-year-old was supposed to be under close staff supervision in June last year at the psychiatric unit of the Brampton Civic hospital.

Tiwari's family claims that he was supposed to be checked on every 15 minutes, but was allegedly left unattended for more than 2 1/2 hours.

They say Tiwari's body was found in a hospital washroom.

The family has filed a $12.5 million wrongful death and breach of privacy suit against the William Osler Health System, which owns the Brampton hospital, and members of its staff.

None of the allegations has been proven in court.

The family's statement of claim alleges the hospital and staff were negligent, by failing to properly supervise Tiwari.

It also alleges that staff accessed Tiwari's personal information without authorization after his death.

The William Osler Health System said in a statement that it had not received notice of legal action from the family and would respond through the appropriate legal process when it did.

It added that it continues to express "sincere condolences" for the Tiwari family's loss and support them to the best of its ability.

"We have shared all findings of our review of the case with the family, as well as the actions we have taken to address the recommendations and enhance our systems and processes," it said. "Further, Osler has co-operated fully with the Coroner's Office."