Police attended shortly afterwards and the man was turned over to the officers, who took him to the Main Street Project detox centre.
Less than four hours later, at approximately 2:15 p.m., Main Street Project staff found the man was unresponsive.
He was sent to hospital where he was pronounced dead.
An investigation by members of the police service’s major crimes unit is continuing.
Police spokesman Const. Rob Carver said the man was medically cleared by Winnipeg Fire and Paramedic Service staff before officers took him into custody.
Police don’t know what the man died from. An autopsy is being conducted Monday afternoon.