The government is stepping up its probe into other construction projects linked to the Chinese contractor of the State Audit Office's (SAO) under-construction building that collapsed in Bangkok during last Friday's earthquake.
Speaking after Tuesday's cabinet meeting, Prime Minister Paetongtarn Shinawatra said she instructed various agencies to investigate all construction projects awarded to China Railway No.10 Engineering Group.
The SAO contracted a consortium of Italian-Thai Development Plc and China Railway No.10 to construct the 2.1-billion-baht building.
"All concerned agencies were instructed to delve deeper to find out how many other projects the company is undertaking," the prime minister said.
She said the collapsed building has cost lives and negatively affected Thailand's image.
Justice Minister Tawee Sodsong has ordered the Department of Special Investigation (DSI) to investigate, she added.
"All buildings in Bangkok must meet legal standards. Safety must be the top priority," Ms Paetongtarn said.
A US military scanning kit detects images of bodies trapped in the collapsed building. (Photo: Fire & Rescue Thailand)
She said a probe would be launched into allegations that steel bars used in the construction of the building were substandard.
Apart from the SAO building, other projects undertaken by China Railway No.10 Engineering Group include the construction of a building of the Office of the National Water Resource and some sections of the Bangkok-Nong Khai high-speed railway project.
Deputy Commerce Minister Napintorn Srisunpang said an initial probe has found that shareholders of China Railway No.10 Engineering Group are linked with 13 other companies.
He said a probe panel set up by the Commerce Ministry will work with the Royal Thai Police's Economic Crime Suppression Division and the Revenue Department to investigate whether the group was involved in any collusion or used Thai nominees.
The ministry will forward the findings to the DSI, Mr Napintorn said, adding an initial check has found that 51% of the group's shares are held by Thais and 49% by Chinese nationals.
Bloomberg reported that the contractors of the under-construction office tower which collapsed in Bangkok used substandard steel bars made by a factory that had been shuttered by authorities.
Samples of two different sizes of steel bars collected from the site of the SAO building failed tests by the Iron and Steel Institute of Thailand for their mass, chemical composition and ability to withstand stress before breaking.
The metal was made by a company whose factory had been shut for other violations since December, Thitipas Choddaechachainun, the head of a working group at the Ministry of Industry, said without identifying the business.
Images of the steel bars shared by the ministry and local media displayed the brand "Sky", made by Xin Ke Yuan Steel Co, which had a factory in Rayong province. Authorities closed the factory in December due to an accident involving a gas tank leak and seized more than 2,400 tonnes of steel.
The 30-storey building was the only building to crumble in the Thai capital in the wake of the 7.7-magnitude earthquake that hit Myanmar. The collapse killed at least a dozen workers and trapped dozens more.
Xin Ke Yuan Steel is the second Chinese company to draw Thai scrutiny. The skyscraper was being built by ITD-CREC, a joint venture between SET-listed Italian-Thai Development Plc and China Railway No.10 Thailand Co. Authorities will collect more steel samples and collaborate with the probe.
