The IJO suffered a setback in 1986 when their temporary abduction of four Soviet diplomats carried out previously on September 1985 ended up in the assassination of one hostage. The KGB promptly retaliated with intimidation and by pressuring Syria to stop its operations in northern Lebanon in exchange for release of the remaining three hostages. This fiasco, coupled by the pressure resulting from tighter security measures and joint anti-militia sweeps implemented by the Syrian Army, the Lebanese Internal Security Forces (ISF) and the Shi'ite Amal militia at the Shia quarters of West Beirut in 1987–88, brought a steady decline in the organization's activities in Lebanon for the rest of the civil war.