Two people have been taken to hospital after a fire broke out at BAE Systems’ Barrow-in-Furness shipyard in Cumbria, police said.
Cumbria Constabulary said the fire at the nuclear submarine shipyard broke out at about 12.45am and was ongoing.
A statement said: “At this time there are no other casualties and everyone else have been evacuated from the Devonshire Dock Hall and are accounted for.”
Vision shared on social media overnight showed flames shooting out from the Devonshire Dock Hall building, with alarms blaring in the background.
A Barrow-in-Furness resident who lives beside BAE Systems’ shipyard said she saw thick black smoke billowing from the building.
Donna Butler, 36, told the PA news agency: “My son came and got me and said that the BAE alarms were going off, so we went.
“It was a lot of black smoke, like really thick black smoke, and it was very loud.”
She said a few police cars and emergency service vehicles were at the shipyard and police were asking people to stay in their homes.
Another resident, Jeff Holt, 43, said the fire “looked pretty serious” and that he could smell burning.
A taxi driver, 53, from Barrow-in-Furness, said traffic was backed up for a mile or two after the incident.
The force advised people living nearby to “remain indoors whilst emergency services respond to the incident and keep doors and windows closed”.
The facility is home to Britain’s Astute-class submarines and Dreadnought programme.
BAE Systems has been contacted for comment.