The PLO's security bodies, of which Force 17 was one, have been decapitated in the past two years by internecine struggle and assassination by Israeli hit squads. Last January Hussein Suleiman, a senior Force 17 commander, was killed by unidentified gunmen in the south Lebanese port of Sidon.
Force 17 is nominally headed by Abu Tayeb, who lives in semi-exile in Amman. His relations with Mr Arafat are strained. Historically Force 17 was never very large. The force was initially designed as an elite bodyguard for the PLO chairman. Then it was extended to protect official premises too.
After Mr Arafat left Lebanon following the 1982 Israeli invasion and went to Tunis, Force 17 lost its original role: it tried to find a different mission and was expanded into a paramilitary force, mainly in south Lebanon. It was to undertake offensive operations against Israeli targets, in part to compete with Abu Jihad, who co-ordinated the outside direction of the Palestinian uprising. Force 17 said it was behind the incursion into Israel proper at Dimona in 1988 - in violation of the supposed PLO renunciation of attacks on Israel.
The Palestinians' internal security has not recovered from other blows. The latest victim was Atef Bsisou, the deputy head of the PLO's unified security structure, who was shot dead within five hours of arriving in Paris on the night of 7-8 June.
The Israeli press openly crowed that this was another successful operation by an Israeli hit team against a man suspected of being implicated in the 1972 Munich Olympic Games massacre. His main job was co-ordinating with Western intelligence agencies, above all the French, according to Palestinian sources.
The vacuum left by the murder of the security chief, Abu Iyad, and his deputy, Abul Hol, has never been filled. They were killed by a sympathiser of Abu Nidal. Security is now entrusted to the lesser figure of Hakem Balawi.Reuse content