MITO, Japan (Kyodo) — Police raided a local office of Mitsubishi Chemical Corp. in Kamisu, Ibaraki Prefecture, Monday over a fatal fire at its ethylene plant last month which killed four workers.
About 50 investigators of Ibaraki prefectural police started the search around 10 a.m., police sources said. They planned to confiscate documents in order to determine whether there were any problems with the company's safety management, the sources said.
According to the investigation, the fire broke out on Dec. 21 during pipe maintenance work, with leaked coolant oil catching fire.
The company submitted a report to the Ministry of Economy, Trade and Industry late last month, in which it admitted that it did not clearly note safety measures in its operational manual.
The report also said 165 tons of coolant oil is believed to have leaked from a valve.
