LONDON, ONT -- There were some dramatic moments at London City Hall Wednesday afternoon as a man was arrested for assault.

Shortly after 2 p.m., London police responded to 300 Dufferin St. and arrested a suspect without incident in Reg Cooper Square.

One person was transported from the lobby of city hall to hospital with unknown injuries.

City officials aren’t commenting on what triggered the incident, but people at the scene tell CTV News that a security guard was punched.