The fire broke out just after midnight on Monday, forcing Pertamina to shut the plant and evacuate around 950 nearby residents. Six were treated at the hospital due to the fire.

Pertamina said in a statement that by Wednesday afternoon, fires in all four affected storage units have been extinguished.

Videos posted online showed massive flames and a huge black column of smoke rising from the site.

The company was conducting a cooling down process and planning to begin preparation to restart the refinery as soon as it is safe to do so, it said.

“Hopefully the Balongan refinery can be operational again after a thorough inspection is carried out,” Agus Suprijanto, a Pertamina spokesman said in the statement.

Pertamina expected the shutdown could be lifted in four to five days as damage was limited to the storage area of the plant and did not affect its oil processing area, company officials said on Monday.

The company has said that only 7% of the refinery’s 1.35 million kilolitres (KL) of storage capacity was affected, and that the tanks that caught fire had been only holding around 23,000KL of gasoline.

Pertamina said national fuel stocks remained secure, and any shortage of fuel to Jakarta, which Balongan supplies, could be made up by refineries in Cilacap and Tuban.

Pertamina said there were no fatalities, though media reported one resident had died from a heart attack that could have been caused by the shock of the explosion.

West Java police said it will investigate the cause of the fire.