Muang Pattaya Marine Office director Ekkarat Khantharo said on Saturday the swimming pool had been the subject of public complaints for a while and their officials inspected it two weeks ago.

The probe found that the pool, in the Golden Cliff House Hotel compound, had a concrete structure and 770-square-metres of pool area that extruded into the sea, he said.

Officials learned that the pool was built in 1995 and the hotel had obtained permission to build it from Pattaya City and had paid tax on it from then until now, he added.

However, he said that according to Article 117 of the 1913 Navigation in Thai Waters Act, it was prohibited to build a building or structure into, above or under the surface of a river, canal, lake, or the sea and its beachfront – unless permission to do so was obtained from the Marine Department.

Accordingly, Ekkarat said the hotel was notified that it had infringed on the Act and a complaint had been filed with Muang Pattaya Police Station on Wednesday. So, police were now investigating the matter.

He said the case could be headed for court as the hotel operator claimed the long-standing structure was there when it took over the property from the previous owner.