Mariano Marcos, the father of the Philippine dictator Ferdinand Marcos, was executed by Filipino guerrillas for alleged collaboration with the Japanese during the US liberation of the islands in 1945. According to the memoirs of Robert Lapham, a reserve lieutenant in the US Army that commanded a Filipino guerrilla unit resisting the Japanese during the occupation, he was "drawn and quartered" with the use of carabaos, with what was left of his body hung on a tree.

The US Army in the Philippines did attempt to enforce a strict policy against vigilante "liquidations" of former collaborators post-liberation, but this was met to varying degrees of success in a lawless Philippine countryside infested by roving bands of heavily-armed guerrillas. As an aside, one Japanese soldier recounted how Filipino guerrillas would execute captured Japanese by slowly cutting off their hands, feet, nose and ears. The same Japanese also recalled makeshift “people’s tribunals” set up in villages, where justice to enemy combatants was meted out in a crude form of mob rule. However, many collaborators belonged to elite political families that ruled the Philippines with American help before the war, and were able to secure the protection of US Army soldiers from vengeful guerrillas and political opponents alike. In the end, President Manuel Roxas issued a general pardon of all accused collaborators in 1948.

Sources:

Lapham’s Raiders: Guerrillas in the Philippines 1942-1945 by Robert Lapham, as cited here

Collaboration, Resistance, and Liberation: A Study of Society and Education in Leyte, the Philippines, Under Japanese Occupation by Elmer N. Lear (1952 thesis)

Anarchy of Families by Alfred W. McCoy (1993)

Jungle of No Mercy: Memoir of a Japanese Soldier by Hiroyuki Mizuguchi

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