SINGAPORE – More than 150 people were evacuated from a Housing Board block in Ang Mo Kio on Friday night after combustible gas leaked into the air.

The Singapore Civil Defence Force (SCDF) said it was alerted to the gas leak near Block 401 Ang Mo Kio Avenue 10 at around 10pm.

When SCDF personnel arrived at the scene, the hazardous materials sensors on a fire engine picked up the presence of the gas in the air.

They then used a water jet and two groundwater monitors to disperse the gas. The water monitors spray water into the air from a stationary point.

More than 150 residents from the block were evacuated by the police as a precautionary measure.

An SCDF spokesman said the source of the leak was identified to be from works being conducted near the block, without specifying what type.

The leak was later patched.

People living in the block told The Sunday Times that there was a strong smell of gas from about 8pm.

The police visited residents on the lower floors at around 10pm to tell them to close their windows.

A resident who wanted to be known only as Mr Greg, a retiree in his 60s living on a lower floor, said he and his wife initially closed their windows on the advice of the police.

But within 30 minutes, the officers returned to tell them to evacuate.

“We were told there was a gas leak that had something to do with the waste system improvement works,” he added.

Notices put up at the blocks in the area said there were works being conducted for the installation of a centralised pneumatic waste conveyance system in Teck Ghee and Ang Mo Kio Avenue 10.

The latest notice put up in October 2022 said that the hoarding and excavation works at Block 401 began that month and are expected to be completed by the first quarter of 2023.

Another resident, who wanted to be known only as Mr Mike, 33, a commodities trader, said there was a strong smell of gas when his family walked past the playground at around 8pm on Friday.

“The police came at around 10pm and told us to evacuate, saying there was a suspected gas leak due to the works downstairs and that there was a possibility of explosion,” he added.

“I was a little bit alarmed, but everything was handled by the authorities in a very calm manner.”

He said residents gathered in open areas away from the block, and were allowed to return to their homes by about 12.30am on Saturday.

One person who felt unwell was assessed on-site by a paramedic, but later refused to be taken to the hospital.

ST has contacted SP Group for comment.