Enbridge gas leak empties buildings near Parliament Hill

A loud hiss of gas could be heard in Ottawa's downtown core near Parliament Hill after an apparent construction accident on Tuesday.

Firefighting crews were on standby as several large office towers were evacuated as a precaution.

The incident is the second major problem to strike Ottawa's core infrastructure as the city prepares to host Canada's 150th birthday party on July 1. Infrastructure woes have prompted questions about whether the city will be ready to host the Canada Day festivities.

Officials said the latest incident was likely triggered when a construction crew working on a new light rail transit project struck an Enbridge line, the CBC reported.

Last June, another light rail construction accident caused a large sinkhole to open up on Rideau Street at the corner of Sussex Drive, a major intersection near Parliament Hill.

"We’re really following the situation very closely right now, and we’re in close contact with the city, and I’m convinced that the city will be ready, and of course under the NCC (National Capital Commission) everything will be ready for hundreds of thousands of people that will be here for Canada Day," Canadian Heritage Minister Mélanie Joly told reporters outside of the House of Commons. "And we’re looking forward to that date. It will be a great moment in our history."

Officials also shut off the Centennial Flame on Parliament Hill as a precaution. Enbridge told the CBC it was working to fix the line by morning.