Fire crews tackled a blaze at former Newcastle nightclub Tuxedo Royale last night.
Five pumps from Cleveland Fire Brigade were called to the fire at the boat - which is now docked on River Tees in Middlehaven, Middlesbrough - around 7.10pm on Wednesday night.
Crews used jets and an aerial appliance to put out the blaze which continued to burn into the early hour of the morning.
The former party boat was once a popular nightclub situated on the River Tyne in Newcastle from the 1980s to 2000s before it was moved to Middlesbrough.
A Cleveland Fire Brigade spokesman said: "We got the call at 7.10pm and sent five pumps and an aerial appliance to the scene.
"Firefighters were still on scene at 3am this morning and we remain on site now carrying out investigations into the blaze with police.
"No one was injured."
Cleveland Fire Brigade and Cleveland Police are still looking into the cause of the fire, but said they are treating it as suspicious.
Cleveland Police acting inspector Alistair Robinson said: "We are treating the cause as suspicious and are working to verify this with the fire brigade.
"Investigations are ongoing and we ask that anyone with information calls Cleveland Police on 101."