Firefighters made fast work of a blaze onboard HMCS Corner Brook, a hunter-killer navy submarine undergoing a major retrofit at CFB Esquimalt.
CFB Esquimalt firefighters and local fire crews were called to the base's graving dock at around 12:40 p.m. Monday.
No one suffered any injuries and firefighters were able to extinguish the blaze quickly.
A public affairs officer for Maritime Forces Pacific said the purpose-built repair facility that housed the vessel was evacuated out of precaution. The fire was traced to an engineering space on the boat, but it's not yet known how it started.
The Victoria-class submarine has been undergoing a retrofit for months as a contractor modernizes it with upgrades like a new mast system and military satellite communications antenna.
The work is expected to be complete by early 2020. It's unclear what impact, if any, the fire will have on the estimated completion date of the project.
Fire inspectors were expected to remain on scene Monday to investigate the cause of the blaze.