Two prominent West Bank mayors were seriously injured today when bombs destroyed their automobiles and an Israeli demolitions expert was blinded when the vehicle of a third Arab mayor exploded as he prepared to examine it.

Nablus Mayor Bassam Shaka, an outspoken Palestinian nationalist whom Israel tried to deport last fall for alleged inflammatory statements, lost both legs in one explosion. Ramallah Mayor Karim Khalaf's foot was amputated after another blast ripped through his car.

While authorities could not immediately determine who was responsible for the bombings, many Arabs and some Israelis saw it as retribution by extremist Jews. Israeli opposition Labor Party leader Shimon Peres was quoted as telling his faction in parliament, "The attacks have lowered Israel to the level" of the Palestine Liberation Organization.

The series of bombings and a fourth explosion that rocked a crowded market in Hebron, injuring seven more Arabs, revived a feud that has simmered between Arabs and Jewish settlers in the Israel-occupied West Bank since six Israeli settlers were slain in a machine-gun ambush in Hebron a month ago today.

Some Arab officials said they feared that open warfare would break out in the West Bank, as Israeli troops tightened security in the territory and Prime Minister Menachem Begin pleaded with the area's 950,000 Arabs and with all Israelis not to draw hasty conclusions about who was responsible for the coordinated early morning attacks.

But Palestinian leaders in the West Bank immediately turned their suspicions on ultranationalist Israeli settlers, some of whom have formed small terror groups bent on killing Arabs in reprisal for the May 2 ambush in Hebron.

Palestine Liberation Organization chief Yasser Arafat said in Damascus, Syria, that he considered the United States "directly responsible for the acts and doings of the Israeli occupation authorities who are escalating official terrorism against the Palestinian people in the occupied territories."

The PLO said it would ask for a U.N. Security Council meeting to discuss the "explosive situation," and it called for a general strike throughout the West Bank on Tuesday, Associated Press reported.

[In Washington, spokesman Hodding Carter said the State Department was "deeply shocked and saddened by these terrible acts" and felt strongly that "those who perpetrated this outrage must be brought to justice."]

Besides Peres, other Israeli opposition figures criticized the attacks in language that indicated they assumed the bombings were the work of Israelis. The small Sheli Party, headed by parliament member Uri Avneri, said "private arsenals" of settlers must be seized to prevent recurrences.

The most seriously injured in today's attacks, Shaka, lost both legs when an ignition-rigged bomb ripped through his car as he started to work shortly after 7 a.m. from his home about 25 miles north of here.

Almost simultaneously another bomb exploded in the wheel well of Khalaf's as he set out for work from his home.Khalaf was rushed to the Ramallah hospital, where doctors amputated his left foot.

Suspecting that booby-trap bombs might have been placed in the vehicles of other Arab mayors. Army troops and a police sapper rushed to the garage where Ibrahim Tawil, the mayor of neighboring El Bira, keeps his car. As they approached it, a powerful bomb exploded, blinding the sapper in both eyes.

Earlier, a hand grenade was thrown into the crowded Arab market in Hebron, injuring seven Palestinians.

Shaka, Khalaf and Tawil are the leading Arab political figures left in the West Bank following the expulsion to Lebannon last month of Hebron Mayor Fahd Kawasme and Halhoul Mayor Mohammed Milhem. Kawasme and Milhem appealed their deportations and Israel's supreme court has ordered the government to show why the expulsions should not be ruled illegal.

Extremist Jewish settlers in the West Bank have long accused all five of the Arab leaders of anti-Israeli incitement, and have openly called for their removal from the occupied territory.

Fear of Jewish terrorism against Arabs in revenge for the Hebron slayings has been rising for several weeks, and Israeli security officials had said they uncovered evidence that small groups of right-wing settlers were plotting to attack Arabs.

Before he resigned as defense minister last week, Ezer Weizman ordered the arrest and imprisonment for three months without trial of Rabbi Meir Kahane, head of the militant Kach movement and the Jewish Defense League, and one of his followers.

Kahane had said at a new conference that the government should form a "Jewish terro group" that would "throw bombs and grenades to kill Arabs" and drive them out of the West Bank and Gaza Strip.

"I haven't the slightest doubt that there are Jews in this country at the moment who are planning things, I have no doubt that there are Jews who will do terrorist acts," Kahane said before he was arrested. He has been held in emergency detention since May 13, but many of his followers are still operating.

Security forces tonight began questioning members of Kach and other extremist Jewish organizations, but authorities stressed it was too early to say who was responsible.

Begin, making his first address as acting defense minister, a role he assumed of yesterday, told his Army general staff today. "We must remember, we are a state of laws. As long as we don't have prima facie evidence against anyone, we should not accuse them."

Begin's government tonight survived a motion of no confidence in the Knesset (parliament) by a vote of 58 to 48.

Peres had introduced the motion for the Labor Party after a review of Israeli policies by Begin, who had opened the debate by condemning the assassination attempts and saying he had ordered an intensive investigation.

Brig. Gen. Benjamin Ben-Eliezer, Israel's West Bank commander, said, "I don't know who the people are behind this. "It's too early to tell."

But West Bank Arab leaders noted that the bombings occurred a month to the day after the Hebron ambush, from the Kiryat Arba settlement near Hebron or from the numerous Jewish outposts built by Gush Emunim, the ultranationalist settlement movement.

"There are terrorist organizations against the Arabs. There is a sort of coordination between these people and the military government. The authorities look the other way, and these people do what they want to the Arabs," said Ali Keishe, secretary of the El Bira municipal council, in an interview.

Keishe was there when the bomb exploded in Tawil's garage. It was apparently booby-trapped just inside the door.

He said the demolitions expert, an Arab Druzed and Israeli citizen named Suleyman Sartawi, was just approaching the door when the bomb exploded. Numerous Druze, Arabs of a sect loyal to Israel, serve in the Army and Israeli border police and hold full Israeli citizenship.

Tawil was standing about five yards away, Keishe said, and was thrown 10 feet.

The operating room of the Ramallah hospital was jammed with emotionally wrought friends and relatives of Khalaf as doctors amputated the mayor's left foot and struggled to save his badly mangled right foot.

Amid the confusion, a stretcher bearing the bloody form of the police sapper was wheeled in, and many of the Arabs, seeing the shredded Israel uniform, cheered.

Teams of Arab Doctors worked side-by-side on Khalaf and the Israeli as angry townspeople crowded against the operating room door seeking information about their mayor.

Underscoring the hatred that has been building in the West Bank between Arabs and Jews was the reaction of the Arabs to an erroneous report that the police sapper had died. The towns people broke out into a wildly cheering demonstration, laughing and clapping.

The Israeli sapper was moved to Hadassah Hospital in Jerusalem, where his condition was described as serious after three operations.

Khalaf's wife sat outside the Ramallah operating room weeping, and would not answer questions. A friend shouted angrily, "It's part of the killing of Arab people by the Israelis. They want to drive us out of our homeland!"

Shortly before noon Israeli troops opened fire on a group of Arab youths who had set up a roadblock near the Ramallah bus station and begun throwing rocks at the soldiers. Ishai Cohen, spokesman for the West Bank military governor, said the soldiers first fired in the air, but that two youths were hit in the legs by the bullets.

Outside the Rafidiya hospital in Nablus, while doctors operated on Shaka, a large group of Arabs gathered and chanted nationalist slogans.

There were scattered demonstrations elsewhere in the West Bank, but troops quickly dispersed them.

In Gaza, Mayor Rashid Shawa and his municipal council resigned to protest the bombings. Shawa said Israel's hard-line policy following the Hebron ambush had only increased violence in the occupied territories, and that he could not govern under those conditions.