Niagara police are investigating a report of an armed person in downtown Thorold and are asking the public to stay clear of the area.

At 11:24 a.m. Sunday uniform officers responded to a report of a person brandishing a weapon.

While en route to the call officers received information that a man was armed with an edged weapon and possibly a firearm and that there had been an altercation between the man and a person on the street.

The male suspect is believed to have then entered a multi-unit residential apartment building at 64 Front Street.

Officers arrived on scene and received information that the suspect had entered an apartment unit within the building.

Police contained the unit and the adjacent ones for safety.

The Emergency Task Unit, crisis negotiators and detectives have since arrived on scene.

Due to the ongoing, active investigation the public is asked to stay clear of the area.

Updates to come.

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