Pan's body was found in the river at the warehouse port of Thanapornchai Co on Phetchahueng Road in Bang Yor sub-district of Phra Pradaeng district.
Medical examiners at the Institute of Forensic Medicine in Bangkok determined he had committed suicide. Family members of Pan confirmed it was him after seeing the body and watching surveillance-camera footage showing Pan jumping off the Rama IX Bridge above the river in Bangkok Friday evening.
Pan's gold Volvo sedan was found parked on the bridge that is part of Bangkok's expressway system.
Pan, 68, was the deputy secretary-general of Matubhum party and former deputy spokesman of the Prime Minister's Office.
A native of Uttaradit, Pan was deputy speaker of the Prime Minister's Office in 1997 and 2000 when Chuan Leekpai was prime minister. Previously, he was a history lecturer at Srinakharinwirot University's Phitsanulok campus and later at Prasarnmit campus in Bangkok.