TERRORISM . . . ABU NIDAL'S "TOP GUN" NABBED

A man thought to be the chief hit man for Palestinian terrorist Abu Nidal has been arrested in southern Lebanon. Security officials there disclosed today that they had seized Mahmoud Khaled Eintour, 48, also known as Abu Ali Majed, the man who allegedly headed the assassination branch of Abu Nidal's Fatah Revolutionary Council. Lebanese officials, who plan to try Eintour on kidnapping and murder charges, blame him for hijacking a French yacht off Gaza in 1987 and arranging the killing of a top Jordanian diplomat last year. Nidal himself tops most wanted lists in the U.S., Europe and the Mideast for attacks that killed dozens of people, including 1985 assaults on passenger terminals at the Rome and Vienna airports in which 17 people died.