The slicks were mainly found on the west side of the island including on Nai Yang, Nai Thon, Mai Khao and Kata Karon beaches.
The Marine Office in Phuket has cooperated with related agencies to clean up the oil and collect evidence to identify the vessel from which it was discharged.
Complaints will be formally filed with Sakhu Police Station today (August 7) and those found responsible will be charged with causing damage to marine creatures, the environment and marine traffic under the Navigation in the Thai Waters Act BE 2456 (1913).
The guilty parties could face up to three years imprisonment and/or up to 60,000 baht in fines. They must also pay compensation for the damages.
Varawut said oil slicks also impacted Surat Thani's Tao and Pha-ngan islands, adding that they are considered important resources.
He warned tour operators to conduct activities with responsibility towards the environment and marine resources and pointed out that their careless actions could trigger the closure of tourist attractions for rehabilitation.
Maya Bay in Krabi was closed for three years due to tour operators' carelessness, he pointed out.
He also asked the Marine Department and Department of Tourism to be strict with tour operators in a bid to prevent damage to natural resources.
“The shutdowns during the Covid-19 pandemic allowed many tourist attractions in Thailand to recover," he said, "But today, somebody got careless and damaged what we have preserved. This situation must not happen again.”