Black waves of crude oil-contaminated seawater wash ashore on a beach on Samet Island, one of Thailand's most popular tourist destinations, on Monday.
PTT Global Chemical Plc, the company in charge of the 16-inch pipeline that leaked the oil, said it detected the spill when crude oil from a tanker moored offshore was being transferred to the pipeline for delivery to a PTT refinery.
"The top priorities right now are to get rid of the oil on the sand and the seawater, and to make sure the spill doesn't spread to other shores," Rayong Deputy Gov. Supeepat Chongpanish told the Associated Press.
"This is a very beautiful, white, sandy beach, so we want to make the spill go away as soon as possible," he said of the Prao Bay shore.
An official with the government's Marine and Coastal Resource Conservation Center was quoted saying that this week's spill is the biggest in Rayong province's history and the first to affect Samet Island.