Toronto police are asking for help tracking down a man who allegedly sexually assaulted an 18-year-old man, threatened him with a weapon, drugged him and held him against his will for 48 hours in downtown Toronto.

Officers began investigating the case on March 14, days after the incident took place the previous weekend in the area of Yonge and Gerrard Sts., Toronto police said in a Wednesday news release.

Police said an 18-year-old man was with an older man in a room when he was sexually assaulted.

The 18-year-old then tried to escape and was threatened with a weapon, police said.

He was then held against his will for 48 hours and drugged with a noxious substance that knocked him unconscious, according to the news release.

Police are looking for Keith Bradimore, 43, of Sault Ste. Marie. He is wanted for sexual assault with a weapon, assault with a weapon, forcible confinement, uttering threats and overcome resistance by administering a drug.

He is described as five-foot-six and 170 pounds with a slim build, brown eyes and short black hair.

Police are warning the public to call 911 immediately if they see Bradimore, adding that he is considered armed, violent and dangerous.

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