At least two people were killed after an elevated road being built in Thailand’s capital collapsed, authorities said Tuesday.

Another 11 people were injured in the accident on Monday evening, according to the Bangkok Metropolitan Administration. Bangkok Governor Chadchart Sittipan said in a news conference on Tuesday that one person was killed at the site and another later died at a hospital.

Authorities are investigating the cause of the collapse, which occurred on the west side of Bangkok. The elevated road had been under construction since 2020.

WEDDING BUS CRASHES IN AUSTRALIA, KILLING 10 AND INJURING 25; COUNTRY'S DEADLIEST SINCE 1994

Chadchart said the debris at the site was being removed after authorities confirmed no one else was still trapped. It could take several days for the rubble to be cleared, he said.

Video footage of the moment of the collapse showed a blue metal structure that appeared to be used for holding the concrete slabs suddenly falling and bringing the whole structure down.

The construction project was commissioned by Bangkok authorities to Tharawan Construction and Npa Construction, according to the contract published on the website of the Office of the Official Information Commission.

"This shouldn’t have happened," Chadchart said while inspecting the site Monday evening. "Someone needs to be responsible for this because someone died ... this wasn’t something unpreventable."

Earlier this year, a construction worker was killed and four cars were damaged in a similar accident in Bangkok, when a slab of concrete fell from a raised road under construction.

In that case, a frame being used to lift the slab snapped, causing the concrete section to fall to the ground below.