The spraying of mosquito repellent is the most likely cause of the fatal fire on the 10th floor at the headquarters of the Siam Commercial Bank (SCB) last Saturday night, according to the police.
National police spokesman Prawut Thawornsiri said Friday morning that the investigation revealed the workers spraying the repellent had used the wrong tools, spraying a mixture that included paraffin from equipment that generated a spark.
He said that specific repellent recipe was normally not popular for use inside a building, because the crew used gasoline to power the spraying equipment. The room also stored a lot of inflammable documents.
Security camera images showed workers spraying the chemicals on the 11th floor around 40 minutes before the fire broke out. The camera on the 10th floor was out of order, so police had to question the workers more to confirm the cause.
The blaze claimed the life of volunteer firefighter Decha Duangchana, who died from smoke inhalation.