Amirudin said the report will be aligned with the findings of the criminal probe before being made public, Bernama reported.

He said the technical probe, led by the occupational safety and health department (DOSH), will cover pipe integrity, ground movement and whether nearby activities exerted pressure on the pipeline.

“We cannot release our criminal investigation yet because it needs to be combined with the technical investigation as there are still areas that need to be identified through the criminal probe,” he was quoted as saying at an e-bike handover ceremony to the Selangor police at its headquarters in Shah Alam today.

On May 27, Selangor police chief Hussein Omar Khan said the police criminal investigation, which looked into possible negligence or sabotage, had been completed, but they were waiting for DOSH to finalise its findings.

The explosion occurred at 8.10am on April 1, causing flames to shoot up over 30m high and temperatures to reach 1,000°C. It took nearly eight hours to extinguish the fire, which left a 10m-deep crater, measuring 21m by 24m.