Transport Minister Phiphat Ratchakitprakarn on Monday ordered an investigation into a scaffolding collapse during the construction of a northern line railway tunnel on Saturday, pledging to blacklist the contractor if operational negligence contributed to the accident.
The incident at the Doi Luang Tunnel site in Chiang Rai occurred while workers were installing waterproofing inside the structure. The collapse left two workers dead and two others injured. Construction has been suspended while authorities investigate.
Addressing the incident, Mr Phiphat noted that the contractors were supposed to maintain a strict safety inspection system under relevant ISO standards at the site. He emphasised that the Ministry of Transport would not shirk its responsibility and had already formed a committee to probe the case.
"A discussion will be held with the State Railway of Thailand, and the investigation is expected to wrap up as soon as possible," he added.
Mr Phiphat pledged to blacklist the project's contractor if they are found to have violated safety measures, stressing the ministry's commitment to the highest operational standards and impartial treatment for all contractors.
He also refuted allegations regarding the contractor's political connections in the area, insisting that the procurement process remains completely transparent.
The Comptroller General's Department, not the Ministry of Transport, was in charge of the bidding process, he added.
Meanwhile, Deputy Transport Minister Phattrapong Phattraprasit travelled to Chiang Rai to inspect the scene.
Mr Phattrapong said authorities are looking into whether technical errors, negligence, or both caused the collapse. He also visited the site to ensure proper medical treatment for the injured and swift compensation for the families of the victims.
Moving forward, officials will discuss the future of the project's construction while strictly enforcing safety measures, particularly requiring a rock mass assessment before any drilling or concrete injection.
The Doi Luang Tunnel is one of four tunnels on the Den Chai–Chiang Rai railway project. The line is expected to open in January 2028.
