Abduction of 4 Professors Was Audacious, Bizarre : Lebanon: An elaborate charade fooled the academics and their security guards as well.

With his hands bound and a gun pointed at his head, Alann Steen turned to his wife and said, “Don’t worry darling, it’s only a demonstration.”

They were the last words Virginia Steen heard from her husband on the day, more than three years ago, that he was abducted from the campus of Beirut University College along with three fellow academics, Americans Robert Polhill, Jesse Turner and Indian-born U.S. resident Mithileshwar Singh, who was later freed.

Polhill’s release Sunday left seven Americans, including Steen and Turner, still in captivity in Lebanon. Journalist Terry A. Anderson, the longest held of the hostages, marked his fifth anniversary in captivity March 16.

Polhill, Steen and Turner were not the first Americans to be kidnaped in Lebanon, nor would they be the last. But their abduction on Jan. 24, 1987, stood apart from Lebanon’s other kidnapings, both for its sheer audacity and for the bizarre manner in which it dramatized, more than any similar incident before or since, the full extent of the lawlessness then prevailing in Beirut.

In an elaborate charade that fooled both the victims and their security guards, gunmen dressed as members of Lebanon’s Internal Security Force seized the four professors from their Beirut campus after luring them to a meeting to discuss arrangements for their safety.

The kidnapers themselves were such convincing actors that, even after being handcuffed, Steen, a journalism professor originally from Arcata, Calif., thought it was all a joke, according to accounts provided by witnesses. Not until the hostages were bundled into the gunmen’s police car and spirited off campus did the terrifying truth of what had happened become apparent.

The abduction stood apart for another reason. Islamic Jihad for the Liberation of Palestine, the name used by the professors’ kidnapers, surfaced for the first time with their abduction. The group has not, at least under that name, kidnaped anyone since.

Terrorism experts have different theories, but many believe that the Islamic Jihad for the Liberation of Palestine (IJLP) is a terrorist hybrid--its members drawn from the older and more active Lebanese Shiite organization Islamic Jihad and from the ranks of radical Palestinian splinter groups. It is also thought to have links to Hezbollah, the Iranian-organized umbrella group for Shiite radicals in Lebanon, and through that connection, to have loose ties to Iran itself.

One theory holds that Islamic Jihad and most of the other Shiite groups under the Hezbollah umbrella are in fact a single, if highly amorphous, entity operating under the deliberate confusion of different names. However, there also are indications that the links between some of the groups have grown tenuous, reflecting divisions that have emerged between radical and more moderate political factions in Iran.

In any case, the audacious manner in which IJLP members kidnaped Polhill, a business professor from Beacon, N.Y., and the other three professors suggested both a high degree of training and preliminary intelligence work.

STRUCTURE OF TERROR IN LEBANON Beginning in 1984, scores of foreigners from 18 nations have been abducted by a dozen different terrorist factions, most of them pro-Iranian Shiite Muslim extremists. Here are some of those factions. HEZBOLLAH: Also called Party of God, it is best-known Shiite group; intelligence analysts believe all Shiite terrorist factions fall under Hezbollah umbrella. Movement was born in Lebanon under guidance of Iranian Revolutionary Guards to help Lebanese Muslims and Palestinians resist 1982 Israeli invasion. Leaders: Sheiks Hussein Moussawi, Abdel Karim Obeid, Sobhi Tufaili. Spiritual leader: Sheik Mohammed Hussein Fadlallah.

ISLAMIC JIHAD: First of many Hezbollah cells to gain world attention, Islamic Jihad (Islamic Holy War) holds American hostages Terry A. Anderson and Thomas Sutherland and reportedly killed British hostage Denis Hill in 1985; responsible for 1983 bombing of U.S. Marine barracks in Beirut and bombings of U.S. Embassy in Beirut in 1983 and 1984, with more than 300 killed; also began cycle of kidnaping Americans in Lebanon with abduction of Frank Regier in 1984. It demands release of 15 Lebanese and Iraqis imprisoned in Kuwait for terrorist bombings; one prisoner is brother-in-law of Islamic Jihad’s leader, Imad Mughniyah.

ORGANIZATION OF THE OPPRESSED ON EARTH: Claimed responsibility last July for killing U.S. Marine Lt. Col. William R. Higgins, a member of U.N. observer unit kidnaped in southern Lebanon in 1988. The group first surfaced in 1986 when it reported kidnaping and executing several Lebanese Jews; it gained notoriety in 1987 when it seized two West German businessmen in retaliation for Bonn’s arrest of Mohammed Ali Hamadi, a leader of 1985 hijacking of TWA flight in which a U.S. sailor was murdered.

ISLAMIC JIHAD FOR THE LIBERATION OF PALESTINE: It claims to still hold two American hostages, Alann Steen and Jesse Turner. The two men and newly released hostage Robert Polhill were all employees of Beirut University College when they were abducted in January, 1987. Polhill is the first American hostage to be set free since November, 1986. Leaders: Unknown.

REVOLUTIONARY JUSTICE ORGANIZATION: Claims to hold two American hostages, Joseph J. Ciccipio, controller at American University of Beirut, and Edward A. Tracy, author and illustrator. A pro-Iranian Shiite group, it may be Islamic Jihad under another name, some analysts believe. It claimed responsibility for kidnaping and later releasing a number of French citizens in 1986 and 1987. Leaders: Unknown.

ARAB REVOLUTIONARY CELLS-OMAR MOUKHTAR FORCES: A pro-Libyan group that claims to hold American Frank H. Reed, director of a private Beirut school who was abducted in September, 1986. Leaders: Unknown.

REVOLUTIONARY ORGANIZATION OF SOCIALIST MUSLIMS: Claimed responsibility for 1985 abduction of Briton Alec Collett, a U.N. aid worker, and hanging him the following year. Leaders: Unknown.