ATHENS, Greece (AP) _ The government on Wednesday identified four Arabs it suspects of being involved in a terrorist attack on a Greek cruise ship and tied the leader to a 1978 killing claimed by the Abu Nidal terrorist group.

Public Order Minister Anastasios Sehiotis said police had been able to piece together events leading up to the attack by gunmen on passengers of the liner City of Poros on July 11. Nine people were killed and 98 were wounded in the gunfire and grenade attack off a Greek island.

Sehiotis said the government suspects that Hejab Jaballa, who holds a Libyan passport, led the guerrilla attack.

Police had also identified Jaballa as taking part in the assassination of an Egyptian newspaper editor in Nicosia, Cyprus, in 1978, he said.

Jaballa's fingerprints from Cyprus were matched with those uncovered in his Athens hideouts, Sehiotis said.

Renegade Palestinian terrorist Abu Nidal said in a magazine interview after the Egyptian was shot that his group was responsible for the assassination. Abu Nidal, whose real name is Sabri Banna, gets much of his funding from Libyan leader Moammar Gadhafi and maintains headquarters in Tripoli.

Sehiotis identified the other three suspects as Aboul Amoud, Adnan Sojod and Merhi Mehieddine. Their nationalities were not known. The minister read a prepared statement and declined to answer reporters' questions.

The statement failed to clarify whether any of the suspects were dead or had fled the country.

Police believe that one or possibly two of the suspects may have died either in an explosion on the ship's bridge as they lobbed hand grenades or in a car bomb that apparently detonated prematurely at a marina near Athens six hours before the City of Poros was scheduled to dock.

Two occupants of the car were killed by the explosion.

The minister said Jaballa arrived in Greece on a flight from Copenhagen June 1. His alleged accomplices arrived from Beirut via Belgrade in May.

All four men rented apartments or stayed in various hotels, changing locations often prior to the day of the ship attack, Sehiotis said.

''All the evidence indicates that Jaballa played the leading role in the terrorist operation since he had all the details of members of his group in his possession,'' said Sehiotis.

Ministry officials distributed copies of photographs from forged passports found in hotel rooms and apartments the men allegedly stayed in and at the site of the car explosion.

Greek police have been reluctant to discuss what terrorist group could be responsible for the attack on the ship. But CIA director William Webster said in Washington last week that it appeared to be the work of the Abu Nidal group.

At a separate news conference, Merchant Marine minister Evangelos Yannopoulos said security had been boosted at all main ports and that commandoes would now be permanent crew members of cruise liners.

He said each ship would have ''five to 10 specially trained commandoes'' aboard responsible for neutralizing terrorists attacks.

Yannopoulos was asked whether a dead 23-year-old French passenger, Laurent Vigneron, was part of the terrorist group. Greek authorities have linked him to the attack, but French officials have said they find no evidence he was involved.

''There are indications - based on the testimony of four witnesses - that he (Vigneron) participated in the terrorist attack,'' said Yannopoulos.

He said an autopsy showed that Vigneron was hit by bullets in his shoulder but these were not the cause of his death. He did not elaborate.

Meanwhile, security at the nation's borders, ports and at Athens International Airport was tight.

Passengers boarding cruise ships and ferries were scrutinized closely and their luggage passed through X-ray machines.