City investigates after window pane falls from Brookfield Place tower

An investigation is underway into what caused a glass pane to fall from a downtown highrise on Sunday, leading to road and transit closures that slowed the Monday morning commute.

A pane of glass from the corner of the 23rd floor of Brookfield Place fell onto the pavement below at about 10:30 a.m. Sunday.

Busand C-Train routes were disrupted by the incident, but all services havereturned to normal, according to Calgary Transit.

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Roads around the building, which were also closed to traffic on Monday, have reopened.

Marco Civitarese, the city's chief building inspector, says there are a lot of unanswered questions.

"Is it around manufacture, is it around installation, or is it around other external factors? That's the probable eventuality of an investigation, so we're looking at that right now," he said.

Two weeks ago, a window-washing crew accidentally smashed a panel on the 51st storey while working at Brookfield Place.

"Two incidents at one scenario is very imposing and certainly daunting, and that we do take that seriously. We do recognize that it's two very separate incidents. The incidents are unrelated," Civitaresesaid.

He says the city's safety response unit and first responders remained at the scene through Monday morning and that Brookfield is co-operating with them.

"We have completed a visual inspection of all glass panels in the building and have not identified any further issues," Brookfield Property Partners spokesperson Andrew Brent told CBC News in an email.

It could take weeks or months to determine what caused Sunday's incident, Civitarese said.

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