[1] He was also a Thai senator and the vice-president of the International Confederation of Free Trade Unions - Asia Pacific Regional Organization (ICFTU-APRO).
On 23 February 1991, the military National Peace Keeping Council (NPKC) staged the 1991 Thai coup d'état against the government, declared martial law, and abrogated the constitution.
Tanong was scheduled to appear at the International Labour Organization (ILO) annual meeting in Switzerland in June 1991 to speak about the restrictions placed on Thai trade union activity.
[1] On 19 June 1991 Tanong's empty car was found near his office in Rat Burana District, Bangkok.
After his disappearance his family feared for his health, as Tanong, age 55, was an insulin-dependent diabetic who did not have his medication with him when he was last seen.