The Egyptian government today accused members of a Palestine Liberation Organization "dissident group," backed by Libya, of carrying out the Egyptair hijacking that ultimately cost the lives of 60 persons in Malta yesterday.

An official statement this afternoon said only that the "dissidents" were "working for an Arab country known for its terrorist practices and for sheltering terrorists."

But a commentary on the government-controlled Cairo radio late tonight was more blunt, claiming "Col. Muammar Qaddafi's Libya" provided "funding and incitement" of the hijackers.

In Washington, meanwhile, Pentagon officials disclosed today that the United States provided highly secret equipment to the Egyptian commandos who stormed the plane.

The officials said the Americans also offered to cover the movements of the rescue transport with warplanes on the aircraft carrier USS Coral Sea in the Mediterranean. They said U.S. "technical support" included portable listening gear enabling the commandos to determine where the terrorists were located inside the aircraft.

[The Egyptians belonged to a special antiterrorism squad trained in the United States and West Germany, according to Egyptian military sources quoted by Reuter.]

Egyptian troops remained on alert today along the Libyan border, and the communique released through Egypt's official Middle East News Agency vowed that "those who did wrong" in this incident "will later know what they brought upon themselves."

Egyptian officials declined to elaborate further, and a number of questions remain unanswered -- including how much the Egyptians know about the hijackers.

Official statements here have tended to distort the events in Malta, claiming that the assault on the plane last night was carried out "successfully" and "without any losses in the lives of passengers or the Egyptian commandos" as a result of the commandos' actions.

The communique says that "only 44 passengers were rescued," but blames that on inadequate facilities at the Valetta airport, which were unable to cope with the fires that broke out on the plane after the hijackers hurled grenades.

Egyptian President Hosni Mubarak said in a statement this afternoon that he was "deeply sorry and sad for the innocent victims who were killed by the cowardly terrorists," and praised "the wonderful heroic act of the Egyptian commandos" who "performed in a way that makes every Egyptian really proud of his armed forces."

Although the terrorists called themselves "Egypt's Revolution" and a letter to a Kuwait newspaper claimed the action in the name of a hitherto unheard of "Egypt Liberation Organization," officials here have refused to consider publicly the possibility that the terrorists might have been Egyptians.

The only public evidence pointing at Palestinians thus far is the belief by several Egyptian passengers and crew that the hijackers spoke with distinctive Palestinian, or in one case Syrian, accents.

But by emphasizing claims that the seizure of the airliner was an externally planned and directed plot, Mubarak's government avoids addressing and perhaps fueling already strong anti-Israeli sentiments here.

The hijackers made no political demands in the hours before the plane was stormed.

By pointing at Libya as the state behind this act of terror, Egypt could build domestic political support for stronger action against Qaddafi.

Mubarak said today he "feels sorry for the involvement of certain Arab states in these criminal practices out of which we gain nothing but destruction."

Cairo radio said tonight that Egypt's action in Malta already had "taught the pirates and the instigators a lesson."

After Egypt put its troops on alert along the Libyan border yesterday, Libya's official news agency claimed that Egyptian helicopters, transport planes, and fighter bombers were moved into a base at Barrani on the Mediterranean coast about 50 miles from the Libyan frontier.

There also were unconfirmed reports here today of large concentrations of Egyptian troops at Soloum, within five miles of the border.

The desert road to Alexandria, the principal route for men and materiel being deployed to the border, was closed to the public yesterday for several hours and reportedly is to be closed again.

Hemmed in by increasingly hostile Algeria and Tunisia as well as Egypt, Qaddafi has been concerned in recent months that they are looking for pretexts to launch attacks against him.

The Reagan administration has approved covert actions to support such moves by his neighbors, according to sources in Washington.

For its part, Libya has rejected any suggestion that it was involved in the hijacking.

Libya's ambassador to Malta attempted to negotiate with the hijackers yesterday before being recalled to Tripoli, according to Egyptian reports. Libyan Foreign Minister Abdul Salaam Treiki condemned the taking of hostages yesterday and said that if the hijackers had attempted to fly to Libya, they would have been refused permission to land.

One Palestinian splinter group that Egyptian officials suggested privately might have been responsible for the hijacking is led by Sabri Banna, also known as Abu Nidal. The Abu Nidal faction is responsible for killing numerous PLO officials as well as Israelis and European Jews. Banna was interviewed by the West German magazine Der Spiegel in Libya less than three months ago.

"It is only a matter of time," Banna said then, until Mubarak "will pay dearly for his treason to Arab history."

Three members of Banna's faction were sentenced for critically wounding Shlomo Argov, Israel's ambassador to London, in June 1982. The shooting triggered Israel's invasion of Lebanon that year.