Jerusalem — The gunmen who seized an Italian ocean liner are members of a PLO splinter group who may be seeking to torpedo Yasser Arafat's moves toward peace negotiations, analysts here said Tuesday. It is believed that the seizure of the Achille Lauro off Egypt Monday was made by seven to 10 armed Palestinians. One of the attackers contacted the Egyptians and demanded that Israel release 50 Palestinian prisoners it is holding. If the prisoners were not released, the hijacker reportedly said, American and British hostages on board would be killed and the ship blown up. There were unconfirmed reports Tuesday that the hijackers had killed two passengers, believed to be Americans.
[At press time, the Syrian government had refused to let the ship dock at Tartus, according to sources at the port. American and Italian envoys had arrived at Tartus, however, in response to the hijackers' demand for negotiations, Reuters reported.]
In Tunis, a spokesman for the Palestine Liberation Organization condemned the hijacking and denied any PLO involvement. Mr. Arafat promised Italian Prime Minister Bettino Craxi in a telephone conversation that he would help free the ship.
Arafat would have much to lose if he had authorized the hijacking.
Italy strongly condemned Israel's bombing of PLO headquarters in Tunisia last week and joined in the European Community's decision after the attack to invite a joint PLO-Jordanian team to Luxembourg to explain the peace proposals pursued jointly by Jordan's King Hussein and Arafat. Egypt's President Hosni Mubarak has pushed the Reagan administration hard to start talking to the PLO and to include the guerrilla organization in any peace talks on the fate of the territories Israel has occupied
Both Egypt and Italy would be deeply embarrassed if it were learned that Arafat's mainstream Al-Fatah group was involved in the hijacking.
Israeli Prime Minister Shimon Peres told reporters he believed the hijacking was part of PLO efforts to sabotage King Husseins' peace efforts.
But Israeli analysts strongly disagreed with the prime minister's comments.
``I do not believe this is an Arafat operation,'' said one former Israeli intelligence officer and PLO expert, who spoke on condition he not be identified. ``It is a politically crazy thing to do for Arafat. It looks like the act of rejectionist Palestinians who object to Arafat's moves.''
It was reported that a group of PLO officials left Cairo in a ship yesterday to negotiate with the hijackers.
On Israel's state-run radio, an analyst said that the hijacking indicated that Arafat had lost control of the Palestinians' military forces.
Israeli officials said they had information that indicated the hijackers were members of a little-known Palestinian group called the Palestine Liberation Front. That group is believed to have split from radical Palestinian Ahmed Jibril in 1977, then further split into three groups -- two pro-Syrian and one pro-Arafat. In Damascus, a spokesman for one Palestine Liberation Front faction denied any involvement in the hijacking.
The Italian ship had left Genoa, Italy Oct. 3 carrying 756 passengers and 339 crew members, according to wire service reports. It sailed to Alexandria, Egypt, where most of the passengers including the only Israeli couple known to be on board, disembarked to travel overland for a day of sightseeing in Cairo. Sometime after the ship left Alexandria and before it reached Port Said where it was to pick up the passengers, it was taken over by the gunmen. It is believed that 330 crewmen and 80 passenge rs, including an estimated 11 Americans, were on board when the hijacking occurred.
Italian officials said they believe the gunmen got on the ship as passengers in Genoa. The Italian Foreign Ministry confirmed Tuesday afternoon that Italian warships had been dispatched to the eastern Mediterranean. Italian planes reportedly were tracking the ship's progress.
No one is sure to which Palestinian faction, if any, the gunmen on board belong. The only prisoner they are known to have demanded by name is Samir Kantari. Mr. Kantari is serving a life sentence for his part in a 1979 attack in which an Israeli and his five-year-old daughter were shot to death by armed Palestinians, according to the Israeli military spokesman. Two of the attackers were killed and two were captured. One was released last May when Israel exchanged 1,150 prisoners for three Israeli soldie rs held by Palestinians since the Israeli invasion of Lebanon in 1982.
Israeli officials in Jerusalem said Tuesday that they had been in constant touch with Egyptian, Italian, and American officials since the hijacking occurred. The Israelis insisted that no one had asked them to release the prisoners they are holding.
Israel was last asked to release prisoners in June, when Shiite Muslim gunmen hijacked an American TWA jet and held its crew and some passengers in Beirut. The Muslim gunmen demanded the release of all Shiite prisoners being held by Israel in Atlit prison. Although both Israel and the United States insisted that no deal was reached with the hijackers of the TWA plane, the Atlit prisoners were gradually freed over the course of the summer after the hostages were released.
The last demand for the freeing of Palestinian prisoners was made Sept. 25 by three Palestinian gunmen who boarded an Israeli yacht in the Cypriot harbor of Larnaca. The gunmen demanded the release of Palestinians captured by Israel on board yachts in international waters. Before their demands could be responded to, however, the three gunmen shot to death the Israelis on the yacht and surrendered to Cypriot authorities. It was following the Larnaca attack that Israel bombed the PLO headquarters in Tunis
Israeli officials said privately Tuesday there was virtually no chance that Israel would agree to release any more prisoners. The government was widely condemned here for releasing the 1,150 Palestinians in May.
Experts on terrorism, academics, and even government officials have frequently said the release was a mistake that both undermined Israeli public morale and encouraged guerrillas to take hostages.
Over the summer, fatal attacks against Israelis have increased within Israel and the occupied territories. The government, under enormous pressure to take action, has reinstituted deportations, administrative detentions, and other measures long abandoned by Israel.
But Israel's most controversial act to date was the strike against PLO headquarters in Tunis, a move that exposed Israel to condemnation in the United Nations and by European nations. The government has been struggling since the Tunis raid to control the political damage, stressing that the act was one of self-defense and bitterly criticizing Mr. Craxi of Italy, in particular, for his strong condemnation of the Israeli attack.
Security forces here scored a major victory over the weekend when they ambushed what was described as a ``terrorist gang'' on Hebron Mountain in the occupied West Bank. Four Palestinians were shot to death and another was captured in that ambush. A military spokesman claimed the group had been responsible for the murder of at least five Israelis and the wounding of another 18 in a series of incidents that have occurred over the past 16 months.
It is unlikely, one observer said, that the government would backtrack on its new get-tough policy by now releasing Palestinians convicted of terrorist acts. Remains of PLO headquarters in Tunisia Spiral of Israeli-Palestinian violence Sept. 25: Gunmen murder three Israeli vacationers aboard a yacht in Cyprus. The three gunmen are identified as two Arabs and one Briton. Anonymous caller claims that Force 17, the PLO's secret service unit, was responsible for the attack. Oct. 1: Israeli jets bomb PLO headquarters in Tunisia. More than 60 people, guerrillas and civilians, are killed and nearly 120 injured. Israeli officials say raid is in retaliation for the Cyprus murders. Oct. 5: Three Jews killed by Palestinians in occupied West Bank, bringing to 16 the number of Israelis killed in the occupied territories since the beginning of 1985. Oct 5: Israeli soldiers kill four Palestinians during an Army ambush in West Bank. Army official announces the action Oct. 7, saying the group was responsible for several attacks on Jews in recent months. Oct. 7: Palestinians hijack an Italian cruise ship with more than 400 people on board. Hijackers ask for release of 50 Palestinians held by Israel. PLO officials in Tunisia denounce the hijacking and deny involvement.