An explosion at Brazil’s state-owned oil giant Petrobras-operated Landulpho Alves Refinery (RLAM) near the northern city of Salvador, Brazil, has injured three workers on Sunday.

The 323,000-barrel-a-day RLAM, which is the Brazil’s second-largest refinery, produces over 30 oil derivatives including diesel, gasoline, kerosene, asphalt, and lubricants.

Currently, an investigation is underway to find the cause of the explosion at the refinery.

Press TV? cited Petrobras as saying in a statement: "The injured were quickly tended to by refinery medical personnel and taken to hospital. The company is providing the necessary assistance."

However, the explosion did not cause any environmental damage, the company said, declining to say if the refinery’s oil production was affected by the accident.

The explosion had occurred in the U-38 hydrogen generation unit during maintenance service, reports Daily Mail.