Parts of Citi Plaza and neighbouring businesses were evacuated for a bomb scare on Monday afternoon.

Dundas Street was also closed from Wellington Street to Clarence Street and Clarence was closed from York Street to Queens Avenue.

There was a heavy police presence in the area shortly after 3:15 p.m. on Monday after a 911 call about two suspicious packages found outside the London Public Library.

London police brought in the bomb disposal robot to examine a backpack and a rolling shopping bag-type cart.

Around 6:40 p.m. a loud explosion was heard, with police apparently detonating the first of the two bags using their explosives.

There are reports that a man has been arrested in connection with the incident, but no charges have yet been laid.

The investigation continues.