A company spokesman said Friday there were no injuries and testing will resume pending an investigation by the company, engine-maker Pratt & Whitney and Transport Canada.
"We remain focused on meeting the CSeries aircraft development schedule and entry into service in the second half of 2015, but safety is the priority, Marc Duchesne said.
The nature of the incident that occurred late Thursday afternoon wasn't immediately disclosed, but firefighters from Mirabel airport responded to a call.
The Transportation Safety Board sent an investigator to the scene to gather information and assess the incident.
Pratt & Whitney in Hartford, Conn., said it is "working closely with Bombardier to understand the incident," but declined to provide any further details. Its geared turbofan engine was certified by Transport Canada in February 2013.
Analyst David Tyerman of Canaccord Genuity said the incident isn't good news for a program that has undergone a series of delays, but the impact will depend on the seriousness of what occurred.
"If it's a six-month delay because they have to re-design the engine because there is something they just found that's not a good thing," he said. "If it's a day or six days to fix something that turns out to be minor then it'll have minimal effect."
Tyerman said the incident could delay the certification and will probably further delay orders, which have been weak as potential customers await flight data from the four test aircraft produced so far.
While customers will know what happened, the lack of details could affect Bombardier's share price, he added.
Bombardier (TSX:BBD.B) shares closed down nine cents at $3.69 on the Toronto Stock Exchange.
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