PATTAYA, Thailand – The oil slick previously reported in waters around Koh Larn has now been found floating in the sea and washing ashore at Jomtien Beach, Chon Buri, on Monday, prompting authorities to warn residents and tourists not to swim while the substance is assessed.

Oil-Like Slick Washes Ashore on Koh Larn Beaches

Pattaya City officials confirmed that the slick was reported both along the shoreline and in the seawater, with significant amounts seen near Jomtien and Koh Larn. Workers were dispatched to collect samples of the black, oily substance, determine how far the pollution has spread, and begin removal efforts from the affected area. The discovery at Jomtien follows the earlier report of slicks around Koh Larn, suggesting the pollution has moved across waters used by tourist boats, swimmers, and visitors travelling between the island and mainland Pattaya.

Authorities have not yet confirmed what the substance is or where it came from, and the city said the assessment was still under way, urging people to exercise caution. Pattaya Deputy Mayor Manoch Nongyai said investigators were considering two possible explanations: an illegal discharge from a vessel, or material drifting into the area from around Laem Chabang. Officials from the Marine Department and environmental agencies have joined Pattaya City in the inquiry.

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Pattaya City has not said when Jomtien Beach will reopen for swimming. Until testing and cleanup work clarify the scale and nature of the pollution, the warning applies to residents and tourists alike. The incident has raised concerns about the environmental impact on marine life and the potential economic repercussions for local tourism operators, as the beaches are among the most frequented destinations in the region. Authorities are expected to provide further updates as the investigation progresses and cleanup efforts continue.

-Thailand News (TN)