The Nicaraguan Democratic Force (, or FDN) was one of the earliest Contra groups, formed on August 11, 1981 in Guatemala City. It was formed to oppose Nicaragua's revolutionary Sandinista government following the 1979 overthrow of Anastasio Somoza Debayle. It merged the 15th of September Legion, which comprised mostly former members of Somoza's National Guard, with the Nicaraguan Democratic Union, an organization of émigrés from the business and professional classes. The new FDN also began assimilating the MILPAS movement, bands led by disenchanted former MAP-ML guerrillas. The FDN military was under the command of former National Guard colonel Enrique Bermúdez. The FDN was heavily backed by the Central Intelligence Agency and the Reagan administration. Famous commanders These are some of the FDN's better-known comandantes: Suicida – Pedro Pablo Ortiz Centeno. Former Guard sergeant, operated in the Jalapa area. Legendary for his eagerness for battle, but never fully adjusted from conventional to guerrilla warfare. Went into virtual mutiny in the fall of 1983, and was executed for committing atrocities. Franklin [Franklyn] – Israel Galeano Cornejo. Regional commander of Jorge Salazar II, considered perhaps the FDN's best commander. Supporter of Tigrillo's pre-FDN band. Helped to lead the late 1989 ouster of Bermúdez and the political leadership. Forged alliances with brother Commandos from ARDE Frente Sur leading to significant battlefield victories. Died in a suspicious automobile accident in 1992 in Northern Nicaragua. Toño – Walter Saúl Calderón López. Former Guard lieutenant, first commander of the Jorge Salazar, later led the Tactical Operations Command. Expelled after supporting a bid to oust Enrique Bermúdez in 1988. Mike Lima – Luis Alfonso Moreno Payan. Ex-Guard lieutenant, commander of the Diriangén. Known for the capture of Pantasma in 1983. Left field command for staff duties after crippling wounds. Tigrillo – Encarnación Valdivia [Baldivia] Chavarría. Ex-Sandinista, already leading a ragged MILPAS guerrilla band before joining the FDN. Commander of the Rafaela Herrera, roaming Jinotega Department. A charismatic leader, credited with recruiting thousands into the FDN. Chronically resentful of Bermúdez's favoritism for ex-Guardsmen, he backed the 1988 mutiny. Mack – José Benito Bravo Centeno. Former Guardsman, commander of the Nicarao Regional Commando, operating in the Ocotal area. Gained a reputation for abuses, coupled with a lukewarm will to fight. Rubén – Oscar Manuel Sobalvarro García. Surviving member of the MILPAS movement. Originally took the nom de guerre "Culebra" (Snake), but changed it due to the CIA's public relations concerns.