According to Petronas, the explosion occurred at about 1.25am. An emergency and fire response team was deployed and the fire contained within 30 minutes.

“The situation is under control, and all relevant authorities have been informed,” it said in a statement, adding that investigations are ongoing.

Pictures and videos of the explosion have been circulating on social media, with internet users saying the blast could be felt as far off as Pasir Gudang.

Kota Tinggi district police chief Supt Ahsmon Bajah confirmed that two people were injured in the incident.

In a statement, he said the victims worked as security guards at the facility.

“They received outpatient treatment at the Pengerang Rapid Medical Emergency Centre,” he added.