Corruption buster Veera Somkwamkid on Tuesday lodged a complaint with police against musician Yuenyong Opakul, aka Aed Carabao, accusing him of encroaching on a public forest in Saraburi province.
Mr Veera, secretary-general of the People's Network Against Corruption, together with officials from the Office of Public Sector Anti-Corruption Commission (PACC), also handed in what they said was evidence to Hin Son police in Kaeng Khoi district.
Their claims of encroachment on national park property include alleged illegal acquisition of land ownership documents.
Mr Veera also filed another complaint with the police against authorities of the Royal Forest Department (RFD) for malfeasance.
He said that the PACC had found that Mr Yuenyong owns possessory rights over a 35-rai plot of land located in the Tab Kwang and Muak Lek Forest Reserve, which he had acquired 21 years ago.
Mr Veera speculated that authorities from the RFD had unlawfully granted the possessory rights to Mr Yuenyong.
He further added that the land was used by adventure tour companies.
According to an unofficial survey, authorities found that dynamite had been used on the mountain during the construction of a 500-metre road.
A source representing Mr Yuenyong said that the musician says he is innocent and that the claims are false.
He is prepared for further legal proceedings, the source said.