Toronto police are investigating a late-night shooting in north Scarborough that left one man in hospital with serious injuries and another in police custody.

Shots rang out just before midnight Monday in a parking lot of a shopping plaza located on Finch Avenue, just east of Kennedy Road.

A passerby saw a man stumble and fall near the railway tracks that are just east of the plaza. The passerby called police but by the time authorities arrived, the man was pulled into a silver Mini Cooper.

Police say they received a call a short time later about a victim who had been admitted to Scarborough General Hospital with a gunshot wound to his buttocks and abdomen. The victim, who is in his twenties, has since been transferred to St. Michael's Hospital in downtown Toronto.

The Mini Cooper that was seen transporting the victim has been located and has been searched by police.

A suspect -- a man in his twenties that is believed to have been inside the car -- is in police custody. Police have also recovered a weapon.

Authorities say they are investigating whether the gun battle that erupted between a two groups of men was caught on a surveillance camera that was set up in the plaza. Investigators say they found numerous shell casings in the parking lot.

The plaza remained closed throughout Tuesday morning while police examined evidence at the scene.

Neighbours said they heard some loud bangs but assumed it was a Victoria Day firework display.

"It was only when I heard it on the news did I realize what was happening," one man told CTV Toronto.

With a report from CTV Toronto's Jim Junkin