Police are trying to track down a man wanted for aggravated assault after he allegedly kicked and punched someone while wearing an Angry Birds costume.

The incident happened around 2:30 a.m. on Oct. 30, 2016 — the day before Halloween — and police are now asking the public for any information or video footage they may have about the alleged assault. They say it left a man with serious injuries, including a concussion.

0109 10:51 Pol Seek Asst W/ Angry Birds Aggravated Asslt Invst, Que...& Peter St Area <a href="https://t.co/L2XYDg4JHh">https://t.co/L2XYDg4JHh</a> —@TorontoPolice

Police say a 24-year-old man from the U.S. was walking eastbound on Queen Street West, near Peter Street, with some friends when they were approached by a man wearing an Angry Birds outfit.

When the 24-year-old commented on the man's costume, police said the suspect allegedly turned around and knocked him to the ground before kicking and punching him.

Const. Jennifferjit Sidhu said the victim was knocked unconscious and suffered a concussion, broken nose and jaw, deviated septum, and stretched retina.

"He's not able to carry on daily functions ... it's quite severe," she said.

Victim was an American

The man was treated in Toronto then returned to the U.S. where he is still receiving treatment, Sidhu said. "Basically, someone visiting our city went back home with very severe injuries."

She said the man told police his comment about the Angry Birds costume was "harmless," but because he was knocked unconscious, he doesn't have a clear memory of the incident.

Angry Birds is a popular video game and movie franchise.

Toronto police haven't provided a detailed description of the Angry Birds costume, but said the man was between five-foot-ten and six-feet-tall.

Police looked for surveillance video after the assault but weren't able to find any images of the suspect.

Anyone with information is asked to contact police at 416-808-5200 or Crime Stoppers at 416-222-TIPS (8477).