Hundreds of revellers had to be evacuated from a nightclub after the ceiling caught fire.
The blaze broke out at the Astoria nightclub in Portsmouth, Hampshire, during its Dirty Disco event at about 1.30am on Wednesday.
No-one was hurt in the fire, which firefighters had extinguished by 3.24am.
One clubber, Joe Greenleaf, posted on Twitter that the fire was started by an entertainer using a "spark chainsaw thing".
He wrote: "So the bloke in astoria who brings out the spark chainsaw thing managed to set the ceiling on fire and send everyone home at 1:30".
The event is described on the venue's Facebook page as "probably the best mid-week club night in Portsmouth" featuring "Stilt Walkers, Fire Breathers and the Biggest Party in The City".
Following the incident, the club posted: "Once again, thank you for everyone's assistance and patience this evening. We have now been given access back to the venue."
Frankie Tazewell posted on Twitter: "Well my shift last night took a turn for the worst, didn't expect Astoria to catch fire".
A Hampshire Fire and Rescue Service spokesman said that the premises had been evacuated before its crews had arrived at the scene.
He said: "Vehicles from Southsea, St Mary's, Portchester and Cosham, including the Aerial Ladder Platform, were called to a fire on the dance floor at a nightclub on Guildhall Walk in Portsmouth.
"Everyone was safely evacuated from the premises after the fire involving ducting was discovered.
"The blaze on the second floor of the three-storey building resulted in smoke logging throughout the nightclub.
"The fire was extinguished using six sets of breathing apparatus, two hose reel jets, two jets and tactical ventilation for smoke clearance.
"After cutting away, the stop message came in at 03:24 with crews set to reinspect the scene later this morning."