The Printworks in Manchester has been evacuated with people forced to leave bars, restaurants and the cinema.
Revellers reported being told to leave the building and a large crowd has gathered on the streets outside the venue.
According to the Manchester Evening News, a sprinkler was set off in the disabled toilets of the cinema within the complex.
This comes hours after three people were stabbed in the Manchester Arndale shopping centre today.
Emergency services are at the incident at the Printworks in the city centre tonight - but police have now said there is no reason for people to be alarmed.
Six fire engines are reportedly present.
A tweet from Greater Manchester Police said: "An evacuation of the cinema at the Printworks that took place earlier tonight is due to a false activation of a sprinkler.
"There is no cause for concern or reason to be alarmed."
