Nine migrant workers from Assam were killed on Tuesday after a scaffolding collapsed at a construction site for the Ennore Special Economic Zone thermal power project in Chennai’s Thiruvallur district.

The scaffolding collapsed at around 5:45 pm, leading to workers plunging nearly 45 feet, J. Radhakrishnan, secretary of the Tamil Nadu Electricity Board, told ANI.

One of the workers had held on to the steel structure and was later rescued and taken to the hospital. He is out of danger, said Radhakrishnan.

“Despite safety features like belts, they suddenly fell,” the official was quoted as saying by IANS.

The workers were employed by Metalkarma Engineering Technologies, a private contractor hired by Bharat Heavy Electricals Limited for the thermal project, The New Indian Express reported.

Assam Chief Minister Himanta Biswa Sarma said that four of those who died were from Karbi Anglong district and five from Hojai district.

“We are coordinating with authorities in Tamil Nadu to bring back their mortal remains at the earliest,” Sarma said in a social media post.

The nine workers were identified as Munna Kemprai, Sorbojit Thausen, Phaibit Fanglu, Bidayum Porbosa, Paban Sorong, Prayanto Sorong, Suman Kharikap, Dimaraj Thousen and Dipak Raijung.

The Kattur police have filed a case in connection with the incident and the site has been sealed to allow structural inspections, unidentified police officials from the Avadi Commissionerate told The Indian Express.

Tamil Nadu Chief Minister MK Stalin expressed condolences to the families of those who died and announced a compensation of Rs 10 lakh.

Prime Minister Narendra Modi also extended his condolences and announced ex gratia of Rs 2 lakh each from the Prime Minister’s National Relief Fund for the families of those who died and Rs 50,000 for those injured.