Fire Rescue Victoria said it responded at 11.15pm on Wednesday after multiple reports of explosions and flames at the Viva Oil Refinery at Geelong in the state of Victoria.

“The fire is not yet under control although is currently contained to the plant,” Fire Rescue Victoria said in a statement, adding the blaze involved “liquid fuels and gases”.

There had been no injuries, and Viva had said there was “no immediate impact on fuel supplies”.

“Specialist hazardous materials crews are currently undertaking atmospheric monitoring and being supported by a Fire Rescue Victoria scientific officer,” the statement said.

The Viva Energy website said the refinery was opened in 1954, and “can process up to 120,000 barrels of oil per day, manufacturing petrol, diesel, LPG, jet fuel, avgas (aviation gasoline) and Low Aromatic Fuel”.

It said it supplies “over 50% of Victoria’s and 10% of Australia’s fuel”.

The fire comes just one week after Viva Energy struck a deal with the Australian government to secure additional fuel during the war in the Middle East.

“We understand just how critical fuel is to keep motorists, farmers and businesses moving,” Viva Energy chief executive Scott Wyatt said after the announcement.

“Our dedicated teams have been working tirelessly to keep our customers supplied from our Geelong refinery production as well as sourcing extra cargoes, managing challenging logistics and responding to rapid market developments.”

Viva Energy has been approached for comment.