BANGKOK (AP) -- An international human rights group is calling on Thai authorities to investigate the disappearance of a prominent environmental activist.
Human Rights Watch says Por Cha Lee Rakcharoen, known as "Billy," has been missing since he was detained last week in Petchaburi province's Kaengkrachan National Park.
Park chief Chaiwat Limlikitaksorn says Billy had been arrested for carrying illegal wild honey but was released because it was deemed a petty offence.
The rights group says Chaiwat himself is under investigation for allegedly masterminding the killing of an activist from Billy's network in 2011.
Police Col. Woradet Suanklaai says a missing person complaint has been submitted but Billy's whereabouts remain unknown.
Copyright 2014 The Associated Press. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.