Police in the northern city of Hai Phong are investigating an explosion at a chemical shed that killed two and injured four, including a Chinese national, on Tuesday.
The explosion occurred within a construction zone at the Hai Phong Thermo-electric plant in Thuy Nguyen District, where another explosion claimed four victims, some two weeks ago.
Cao Van Nin, one of four recently injured, said the blast took place at around 8 a.m. when he and seven other workers were preparing approximately 60 chemical drums to be moved to another storage facility.
Nin said the blast sent him flying into a corner of the shed. He was later rushed to Thuy Nguyen General Hospital along with the rest of the injured.
Le Van Minh and Do Thi Thuy, two workers, died on the spot, witnesses said.
Tran Huy Nam, director general of Hai Phong Thermo-electric plant, said the explosion was probably caused by a volatile solvent brought onto the site by the Chinese-owned contractor Dong Phuong Company.
"The contractor didn't comply with safety regulations properly by using the solvent without reporting it to the plant," Nam said.
As the incident took place during the contractor's construction, it should be held responsible, according to Nam.
In the meantime, Bui Van Vi, vice chairman of Thuy Nguyen District's People's Committee, said the plant had to take responsibility especially considering its use of part-time foreign workers.
According to Nin, all of the eight workers worked for VND70,000 (US$3.6) a day without contracts or benefits.
On July 17, a gas explosion at the thermo-electric plant also killed two workers and injured two, all of whom were foreigners. The men had been in the middle of welding components of a de-sulfurization system when the blast erupted.
The Hai Phong Thermo-electric plant opened in December 2009. Technical problems put plant operations on hiatus until last month. Following its re-activation, portions of the plant have remained under construction.