Firefighters in Indonesia are working to put out a massive fire that has broken out at one of the country's largest oil refineries.

The fire broke out at the Balongan refinery, run by state oil firm Pertamina, at 00:45 local time on Monday (17:45 GMT Sunday).

At least five people are injured and around 950 residents have been evacuated to safety. A handful of people have been reported missing.

The cause of the fire remains unclear.

TV footage and videos on social media showed the fire still raging on Monday morning with a plume of smoke rising high above the refinery, located in West Java province.

"We smelled a strong fuel scent first, so strong that my nose hurt, while we heard lightning strikes," one nearby resident told local news outlet Metro TV, according to a Reuters report.

According to the regional disaster management agency, five people were being treated in hospital for serious burns with another 15 with minor burns.

The injured are both nearby residents and people who were on a road near the refinery when the fire broke out.