By allowing one faction of the military to get rich on government contracts, Chatichai provoked a rival faction, led by Generals Sunthorn Kongsompong, Suchinda Kraprayoon, and other generals of Class 5 of the Chulachomklao Royal Military Academy to stage the 1991 Thai coup d'état in February 1991, charging Chatichai's government as a corrupt regime or 'Buffet Cabinet'. The junta called itself the National Peace Keeping Council. The NPKC brought in a civilian prime minister, Anand Panyarachun, who was still responsible to the military. Anand's anti-corruption and straightforward measures proved popular. Another general election was held in March 1992.

The winning coalition appointed coup leader Suchinda Kraprayoon to become Prime Minister, in effect breaking a promise he had made earlier to King Bhumibol and confirming the widespread suspicion that the new government was going to be a military regime in disguise. However, the Thailand of 1992 was not the Siam of 1932. Suchinda's action brought hundreds of thousands of people out in the largest demonstrations ever seen in Bangkok, led by the former governor of Bangkok, Major-General Chamlong Srimuang.

Suchinda brought military units personally loyal to him into the city and tried to suppress the demonstrations by force, leading to a massacre and riots in the heart of the capital, Bangkok, in which hundreds died. Rumours spread out as there was a rift in the armed forces. Amidst the fear of civil war, King Bhumibol intervened: he summoned Suchinda and Chamlong to a televised audience, and urged them to follow the peaceful solution. This meeting resulted in Suchinda's resignation.