A three-storey scuba diving boat sank after catching fire off Hong Kong’s scenic Jin Island in Sai Kung on Saturday afternoon, with 15 people on board rescued.

The 22.7-metre (75 foot) vessel, which was carrying many scuba tanks, could be seen engulfed in flames and billowing smoke in video clips of the incident circulating online. Several of the tanks exploded in the fire, creating a huge mushroom cloud.

Police sources said the force received a report at 4.29pm that a boat was on fire southeast of Jin Island and that marine police were investigating the cause.

The vessel’s 15 passengers were rescued by another nearby boat, and were subsequently ferried to the marine police base in Sai Kung.

The waters around Jin Island, known for its sea caves and natural arches, are popular with scuba divers.

The blaze off Sai Kung was actually the second fire to break out on a boat on Saturday. In the wee hours of the morning, a 49-year-old Scottish man was forced to flee for his life after his three-storey boat moored at the Kwun Tong typhoon shelter caught fire.

Police sources said firefighters were able to put out the blaze, which an initial investigation found had started when the man’s laptop, which was connected to the boat’s electrical system, short circuited.

The sources said the man was unhurt and declined to be sent to hospital.

In October, a blaze broke out on a 17-metre boat moored off a shipyard at the Aberdeen South Typhoon Shelter, and in June, a cargo ship carrying metallic waste burst into flames in Victoria Harbour. No one was injured in either fire.