Five people were injured when their boat carrying 100 litres of fuel burst into flames off a coastal city in the Philippines.

The crew of eight members were departing on the Lady Radia vessel from Barangay Rio Hondo in Zamboanga City to transport goods to Baluk-Baluk Island in Basilan province when an explosion ripped through their boat on July 6 evening.

Dramatic CCTV footage shows the blast erupting in the boat's cabin as several people - including one on fire - jumped overboard.

The Philippine Coast Guard (PCG) Southwestern Mindanao and the local Bureau of Fire Protection (BFP) responded to the blaze and extinguished it four hours later at around 11:30 pm.

Five people suffered burns of varying degrees and were rushed to the Zamboanga City Medical Centre for treatment. The other three crewmen were safe, the PCG said.

In a statement, the PCG said: 'When the BFP declared fire out at around 11:30PM, the Marine Environmental Protection Force-Southwestern Mindanao and Coast Guard Sub-Station Rio Hondo inspected the vicinity waters for possible traces of oil spill and yielded a negative result.'

Police Major Julius Dao-an, station commander of the Zamboanga City Police 11, said: 'The boat was loaded with assorted goods and gasoline. When the engine was started, it sparked and triggered a fire and explosion. The passengers jumped overboard.'

Superintendent Christopher Morales, District Fire Marshall of BFP-Zamboanga, said: 'We are still obtaining statements from witnesses to establish the cause of the fire.'