Jakarta: Nearly 150 people were injured and around 7,000 fled their homes after an explosion at an oil refinery in eastern Java island early on Saturday, police said. The blast took place at a joint Pertamina-PetroChina oil refinery in Bojonegoro district just after midnight, as workers tried to contain a gas leak by setting it alight, said local police chief Rumhadi. There were no deaths reported, but nearly 150 people were hospitalised suffering from respiratory problems after inhaling gas, said Rumhadi, who like many Indonesians goes by one name. "Police are still investigating the cause of the accident," he said. Although the fire has been put out, around 7,000 residents from 10 villages in the district 575 kilometres east of the capital, Jakarta, will not be allowed to return to their homes and must stay in government offices until the area is safe, Rumhadi said. Indonesia's Pertamina and PetroChina of China, both state-owned energy companies, did not immediately comment on the blast.