Toronto police are searching for a man who allegedly made a false report about another man with a gun downtown last week, triggering a major police response that brought the downtown core to a standstill for several hours.

The man allegedly made the call to police from a pay phone near the corner of Spadina Avenue and Cecil Street at about 1 p.m. last Thursday. Investigators said Monday morning that they want to question him in connection to an ongoing public mischief investigation.

According to police, the man called to say that a man with a gun had forced a person into a building in the area of King and Charlotte streets. The response included heavily armed emergency task force officers and shut down roads, sidewalks and public transit for several hours.

The man allegedly made a call to police from a pay phone in the area of Spadina Avenue and Cesil Street. (Toronto Police Service)

Police have since determined the call was indeed fake. Investigators have published security camera images of the man and are asking for the public's help to identify him.

He's described as between 5 feet, 10 inches and six feet, 2 inches tall with a medium build. He was wearing glasses. a green camouflage jacket, black pants, black shoes, a black baseball cap and a black backpack when he called police. He had what police describe as a "vintage-style hybrid bicycle" with a black rear mud guard.

Anyone with potentially useful information is asked to call Toronto police's 54 Division or leave an anonymous tip with Crime Stoppers.