PORT ARTHUR, Texas (AP) — Three workers were killed and two others injured after a scaffolding gave way at a Texas construction site, authorities said.

First responders were called to the Port Arthur LNG site early Tuesday for an industrial accident involving Bechtel workers, according to a Jefferson County Sheriff’s Office statement posted on social media.

When a scaffolding gave way, three workers fell to the ground and two of them died on the scene, the sheriff’s office said. The third worker died at a hospital. Two other injured workers who were still on the scaffolding were taken to a hospital with injuries that were not considered life-threatening.

The accident is under investigation and the Occupational Safety and Health Administration has been notified, the sheriff’s office said.

Bechtel said in a statement that work at the site was stopped immediately and all workers were sent home early to be with their families. The company said it was cooperating with authorities and has launched its own internal review.