Firefighters were tackling a blaze on Thursday at Warner Bros studios north of London, where the Harry Potter films were shot
Fifteen fire engines were at the Leavesden studios in Hertfordshire where the fire started late on Wednesday night, the local council said.
The set was not being used at the time and there were no injuries, it added.
No further information was immediately available from the studios on Thursday.
All eight of the Harry Potter films were filmed at Leavesden, along with other movies including some in the James Bond, Fast and Furious and Mission Impossible franchises.
The studio was converted from an aircraft factory by the producers of the “Golden Eye” Bond film in 1994.
Firefighters tackle blaze at Warner Bros UK studio