* Sunday fire kills five, injures one
* Pengerang oil refining complex shut down
* Full commercial ops were set to begin this year (Adds comments from Petronas-Aramco venture)
KUALA LUMPUR, March 16 (Reuters) - A fire killed five people at an oil refining complex in southern Malaysia owned by Petronas and Saudi Aramco commercial operations this year.
It was the second fire in less than a year at the $27 billion Pengerang Integrated Complex (PIC) in Malaysia's southern state of Johor.
The massive project includes a refinery, which will process around 300,000 barrels per day of crude oil when fully operational, and petrochemical plants with annual production capacity of 3.3 million tonnes.
Petronas and Saudi Aramco each have a 50% stake in the PRefChem joint venture, which owns and operates the refinery and some petrochemical plants at PIC.
The Johor state fire and rescue department said the fire and a blast occurred on Sunday night at the diesel hydro treater unit, which was removing sulfur from raw diesel using hydrogen gas.
Other than the fatalities, one person has suffered burns, the fire department said, adding that the cause of the fire was under investigation.
Pengerang Refining and Petrochemical (PRefChem), the joint venture, said a thorough investigation was ongoing and that it was cooperating with authorities.
"The emergency response team is working closely with the relevant authorities and the situation is under control and the site is shut down," it said in a statement.
It also confirmed the five deaths and the injury.
In April 2019, an explosion and fire occurred at the plant's atmospheric residue desulphurisation unit (ARDS), a unit that removes sulfur from fuel oil, which is then used to produce gasoline. There were no casualties then.
The ARDS has been scheduled for operation by mid-2020, and full commercial operations for PRefChem was targeted for the second half of 2020.
Malaysia's Pengerang peninsula sits between the Malacca Strait and the South China Sea, through which almost all the Middle East oil and gas bound for northern Asia's industrial powerhouses of China, Japan and South Korea is shipped.
The PIC project is state energy firm Petronas' biggest investment in Malaysia.
Saudi Aramco came on board in 2017, agreeing to pump in $7 billion in its biggest downstream investment outside the kingdom. It also agreed to supply up to 70% of the crude feedstock requirement of the refinery.
(Reporting by A. Ananthalakshmi and Mei Mei Chu; Editing by Christian Schmollinger, Tom Hogue, Giles Elgood and Louise Heavens)