The cause of death has yet to be released.
Pian, along with his son Prab Keesin, was facing charges of extortion and criminal activity carried out by a criminal association after military personnel and Region 8 Police raided his home in August.
Pian was suspended from his post as Mayor of Patong in September last year and found guilty of vote fraud in March this year. However, the court issued him a “yellow card”, allowing him to run for re-election.
He ran for mayor again in April, but lost to current Patong Mayor Chalermluck Kebsup.
Phuket Gazette