A police watchdog is investigating the death of a man who was found unresponsive while in police custody.

According to Edmonton Police Service, officers were called to a home in the area of 45 Street and 22 Avenue on Thursday around 11:30 a.m.

They were told a man would not leave the home, whose residents he knew. He was said to be intoxicated and acting aggressively.

Officers removed the 23-year-old but did not press charges.

Later that day, around 4:25 p.m., officers were contacted by the same people who said the young man had returned and entered the property without permission.

This time, officers took the man into custody for uttering threats and being unlawfully in a home.

On Friday, he was found unresponsive in his cell during a 7:40 a.m. routine check.

First aid was administered by the on-duty paramedic and staff until EMS arrive, who treated and transported him to hospital.

He was pronounced dead at 2:05 p.m.

Officials are awaiting the toxicology and autopsy results, but said the man had no observable trauma other than minor bruising believed to be caused by medical intervention when he was found unresponsive.