Updated

A fire caused by explosions in one of the world's largest petrochemical industrial estates have killed 12 and injured more than 100 people in eastern Thailand.

The Saturday blaze forced an evacuation of workers and more than 1,000 residents near the Map Ta Phut industrial estate, Thailand's largest industrial park, in Rayong province, 180 kilometers (110 miles) southeast of Bangkok.

Rayong governor Seni Jittakasem said Sunday authorities were investigating the cause of the explosions that occurred when workers were cleaning a chemical tank at Bangkok Synthetics plant, a synthetic rubber manufacturer.

He said all evacuees have returned home.

The fire was put under control after four hours of chemical burning that sent plumes of thick smoke over a wide area.