MIDDLESEX CENTRE, ONT. -- An emergency preparedness exercise was held in London on Thursday, with a loud emergency siren sounding.

The areas around the Labatt Brewery, Harris Park and Carfrae Park were closed to the public between 8 a.m. and 1 p.m. for the exercise.

The City of London, first responders and Labatt Brewery were involved in the field exercise, including Hazmat teams from the London Fire Department and Labatt Brewery, to test handling of an ammonia leak.

Dave O’Brien, director of Emergency Management and Security for the City of London, said in a statement, “Our team work with our community partners is part of our ongoing commitment to be better prepared should an emergency occur, so we can work as quickly as possible to protect our citizens. When it comes to safety, we are all aligned.”

The exercise was testing the Labatt Emergency Notification Siren and the city’s emergency planning in the areas of preparedness, response and recovery.

The emergency siren was expected to sound for about three minutes between 9 a.m. and 10 a.m., and be audible to anyone within two kilometres of the brewery. Residents were warned to keep sensitive pets indoors.