Tyne and Wear Fire and Rescue Service has confirmed the fire is now being treated as suspected arson.
Thick plumes of smoke could been seen across the city after the fire broke out near the Ropery, in the Deptford area of Sunderland.
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Crews were initially called at 1.40pm on Saturday, February 15, and didn’t leave the scene until almost 4pm.
It shows the flames engulf the boat’s cabin.
The fire service has confirmed no one was aboard the boat and nobody has been injured.
A spokesman for the brigade said: “We are compiling the information from crews now but the incident is being treated as suspected malicious ignition.
“Three crews attended the fire: two from Sunderland Central and one from Marley Park.
“Crews had left the incident by 3.55pm.”
Smoke could be seen from the Stadium of Light nearby although Sunderland AFC is playing away at Oxford on Saturday afternoon.
One man, who asked to remain anonymous, said he watched firefighters struggle to access the boat.
He said: “I don’t know what’s caused it but there’s been a few fires along the river banks recently.”