UPDATE: The factory is already back up and running, a spokesperson told This is Grimsby on Thursday, adding no long-term disruption is expected to operations.
Young's Seafood said it was investigating a fire which broke out at a factory in Humberstone Road, Grimsby, in the UK.
About 40 firefighters were involved in tackling it, and were on site for four hours, said the newspaper.
The fire spread through the factory's extracting system, stretching across 150m of the building's roof, leaving a hole, it said.
The damage is not extensive, due to the size of the factory, Mark Toplass, group manager for Humberside Fire and Rescue told the newspaper.
"Everyone from the site was evacuated and accounted for and we want to reassure people that nobody was hurt," a spokesperson said. "We are now conducting a full inquiry into why this incident occurred."