Possibly formed in early 1983 and reportedly led by Imad Mughniyah, a former Lebanese Shi'ite member of Palestinian Fatah's Force 17, the IJO was not a militia but rather a typical underground urban guerrilla organization. Based at Baalbek in the Beqaa valley, the group aligned 200 Lebanese Shi'ite militants financed by Iran and trained by the Iranian Revolutionary Guards' contingent previously sent by Ayatollah Khomeini to fight the June 1982 Israeli invasion of Lebanon. However, senior Iranian officials denied the alleged connections. For instance, Mehdi Karroubi claimed that Iran had not been related to the group.