Ontario's Special Investigations Unit says it is looking into the circumstances behind a death on Friday after a man plunged from a Toronto balcony during a police investigation.

According to the SIU, Toronto police said officers responded to a 15th floor apartment in a high-rise on Shuter Street, near Parliament and Queen Streets, shortly before 9 a.m.

Officers arrived at the unit and heard shouting. A short time later, a male was found on the ground without vital signs, the SIU said.

Toronto police Const. Tony Vella said that police were dispatched to the apartment complex after receiving reports of a man with a gun.

Vella could not share more information about the incident, citing the SIU investigation, but said no shots were fired.

A neighbour told CTV Toronto's Ashley Rowe that a resident of the building had jumped from the apartment balcony.

The SIU is an arm's length agency that investigates reports involving police where there has been death, serious injury or allegations of sexual assault.

Anyone with information or who may have witnessed this incident is asked to contact SIU investigators at 416-622-1898.