SUBANG JAYA: It took just an hour of heavy rain to almost completely flood the crater at ground zero, where work is ongoing to extract the final section of a gas pipeline in Putra Heights.

About half an hour after reporters left the site following a visit to ground zero, a heavy downpour began at around 2pm.

By approximately 3pm, while the rain was still falling, a source revealed that the crater had almost completely flooded, sharing a photo via WhatsApp.

At least 50 members of the media were allowed into ground zero today - a move that Selangor police chief Datuk Hussein Omar Khan believed would help them better understand the immense challenges faced by the joint investigation team probing the incident.

The group was escorted from the main road along Persiaran Harmoni to Jalan Putra Harmoni 1/3, adjacent to the crater.

Police then requested that members of the media surrender their mobile phones before being granted access to the site where the investigation was taking place.

Homes located near the crater bore evidence of the devastating heat from the flames, which the Fire and Rescue Department said reached over 1,000 degrees Celsius.

Some of the houses closest to the site had only their cement walls still standing.

There were also signs that the heat had melted metal, believed to be remnants of vehicles, with several pieces of melted metal and alloy seen strewn on the ground in front of the damaged houses.

Earlier today, it was reported that rain remains the biggest challenge for investigators at ground zero, where the gas pipeline exploded.

Hussein was quoted as saying that it had rained on 20 out of the 28 days since investigations began at the site.

He also told reporters that once it rains, it takes nearly half a day to pump out the stagnant water from the crater before excavation work on the affected pipe can resume.

He added that the rain had also made the ground unstable, further slowing down operations at the scene.

On April 1, a massive fire involving a Petronas gas pipeline broke out in Putra Heights, Selangor.

Videos captured dramatic scenes of orange flames shooting skywards from the pipeline site, visible from kilometres away.

The incident destroyed 81 homes in the vicinity of the blast, with another 81 partially damaged, and 57 others affected by the heat of the flames.