Four Workers Die in TB Simatupang Water Tank, Police Test Gas Samples

JAKARTA, KOMPAS.com — Police are still investigating the type of gas suspected of causing the deaths of four building project workers on Jalan TB Simatupang, Jagakarsa, South Jakarta.

Water samples from inside the tank are being examined at the Forensic Laboratory to identify the source of the gas that caused the victims to lose consciousness.

At the time of the incident, one victim fell while opening the bolts on the tank cover. Then, three others who tried to help also fell in.

The forensic laboratory examination is aimed at identifying the type and source of the gas that caused the victims to suffer shortness of breath.

“The results will be announced once available,” said Indra.

In addition to the police, Indra mentioned that the DKI Jakarta Manpower Agency and the Indonesian Ministry of Manpower are also examining the water samples.

Police have not yet determined any criminal offence in this case. So far, police have questioned two project foremen. Next, police have scheduled an examination of the building owner.

In the examination, police will ask the building owner to bring documents related to building permits, along with occupational safety and health (K3) standards.

It was previously reported that four building project workers on Jalan TB Simatupang, Jagakarsa, died in a workplace accident on Friday morning (3/4/2026).

The four victims who died were initialled YN (32), MW (62), TS (63), and MF (19).

The Head of the Criminal Investigation Unit (Kasat Reskrim) of the South Jakarta Police, AKBP Mohamad Iskandarsyah, confirmed the discovery of the four workers’ bodies.

“Correct, there was a discovery of bodies this afternoon. They are currently being autopsied,” said Iskandar to Kompas.com on Friday.

Jagakarsa Police Chief AKP Nurma Dewi explained that the incident began when one worker fell into the clean water tank while dismantling its cover.