SUBANG JAYA: Selangor police chief Datuk Hussein Omar Khan has confirmed that excavation work was being carried out to change sewer pipes approximately 30 metres from the Putra Heights explosion site.

He said two pieces of equipment were used - an excavator, which was left at the site and subsequently buried, and a backhoe, which was removed before the explosion.

The work, which had been approved by the city council beforehand, was halted on March 30.

He added that the police have identified the developer, contractor, subcontractor, and workers involved in using the backhoe and excavator for the sewer pipe replacement, and they have been called in for questioning.

"As we are aware, on April 1, a massive explosion occurred, causing a significant impact that resulted in a large crater approximately eight metres deep and 70 metres in diameter.

"The explosion happened underground, where there are three three Petronas pipelines carry methane or natural gas. One of these pipelines exploded.

"Whether the excavation work contributed to the explosion is a matter that requires further investigation to identify other possible factors," he said at a press conference at the incident command post today.

He added that additional evidence needs to be gathered as investigators excavate the site, where physical clues may be found to determine whether soil excavation activities played a role in the explosion.

At present, stabilisation works are underway because the massive explosion disrupted the area's original structure and landscape, rendering the site unstable.

He said the police need to excavate the site to determine whether anyone was inside the excavator, but this will only be done after April 15.

"So far, we have taken statements from 56 witnesses, including victims who were present at the scene, as well as contractors and workers in the area.

"At present, we have identified one key witness who was at the scene when the explosion occurred - a security guard stationed in front of a newly constructed shop lot. This means he was about 30 metres from the explosion site at the time and was also injured.

"The police are gathering information and statements from this witness to determine whether any activities - such as burning, excavation, or other actions - could have triggered the explosion. We need more time as we continue efforts to stabilise the ground and conduct a more detailed investigation," he said.

Hussein added that they are also reviewing 20 dashcam recordings and other related videos provided by independent witnesses.

He said these videos helped them identify a witness who was present at the scene, and he urged the public to come forward if they have any additional information, images, or videos.

"We want to determine who else was present at the scene during or before the incident and whether any activities took place that could have led to the explosion," he said.

As for whether the excavation work was conducted on reserve land or road reserve land, he said this is still under investigation.

Regarding viral claims that excavation work took place on the morning of Hari Raya, he said the police have obtained the video in question and have also interviewed the witness who made the claim.

"The witness was in the area visiting for Hari Raya and saw the backhoe that morning. However, he was unsure whether any work was actually being carried out.

"We have identified the backhoe owner, who removed the machine for repairs due to reported damage. While we can confirm that the backhoe was present in the area, we have yet to determine whether excavation work took place," he said.

"Further investigation is needed to establish whether any digging activities, if they occurred, could have triggered the explosion. The excavator was indeed at the site because some work had not been completed," said Hussein.

Meanwhile, he said the technical report, which will be led by the Public Works Department, is estimated to take approximately two weeks to produce a preliminary report in collaboration with other agencies.

He added that they would need another two weeks to complete a full report due to the complexity of the situation.

On April 1, a massive fire broke out at a Petronas gas pipeline in Putra Heights, Subang Jaya, causing widespread panic as flames shot up in the air.

The heat from the flames - visible from kilometres away - melted plastic and metal within a wide radius of the pipeline.

A total of 227 houses and 365 vehicles were damaged in residential areas near the pipeline.