TERROR RETURNS TO ISRAEL\25 killed, 77 injured in Israel.

Byline: Serge Schmemann The New York Times

A six-month lull in terror attacks in Israel was shattered in the early morning Sunday when militant Muslim suicide bombers detonated pipe bombs in Jerusalem and Ashkelon, killing 25 people and wounding 77, some critically. Among the dead were two Americans.

Messages received by news organizations said the attacks were an act of vengeance for the death of Yahya Ayyash, a Palestinian known as "the Engineer" for the bombing attacks he organized in recent years against Israel. Ayyash, who belonged to an armed wing of the militant Islamic movement Hamas called the Qassam Brigades, was killed Jan. 5 by a booby-trapped mobile telephone.

Although government and opposition leaders joined in condemning the attacks and both sides refrained from recriminations, there was no question that the revival of terror attacks, with the worst carnage to date in suicide bombings, would have a profound impact on the campaign for national elections May 29.

While Prime Minister Shimon Peres and his Labor Party have held a sizable lead in public-opinion polls over the conservative Likud opposition since the assassination of Prime Minister Yitzhak Rabin in November, all political pundits have said this could change sharply and rapidly if Palestinian terrorists struck again.

Immediately after the bombings, Peres closed Israel to Palestinians from the West Bank and Gaza Strip and suspended all contacts with the Palestinian Authority until after the funerals for the victims.

But he also vowed at a news conference to continue with negotiations toward a full peace with the Arabs, saying, "We will cope with the pain and suffering, and we will continue with the only way we have, to which there is no alternative."

Among the first to call Peres and offer condolences was Yasser Arafat, the chairman of the Palestinian Authority.

"This is not a military operation," Arafat told reporters. "This is a terrorist operation. I condemn it completely. It is not against only civilians, but against the whole peace process."

In Washington, Secretary of State Warren Christopher called the bombings "the desperate acts of desperate people who would try to prevent the march of peace in the Middle East." He added, "I have a message for them today: You are cowards, and you will not succeed."

Christopher said that he had spoken with Peres and Arafat and that both men had assured him of their "commitment to stay on the path to peace."

In a statement released at the White House, President Clinton said the bombings "offend the conscience of the world."

"They must not only be condemned," he said, "they must be brought to an end."

The bombings Sunday took the highest toll of any of the eight previous suicide attacks mounted by Muslim militants of Hamas or the smaller Islamic Jihad since April 1994.

The explosion in Jerusalem, by far the bigger of the two, pulverized a bus approaching the main bus terminal at 6:42 a.m., scattering debris and flesh over a 50-yard radius and killing 23 passengers, including a bomber. Residents on the other side of Jerusalem reported being awakened by the blast, and windows of a nearby apartment block were shattered up to the fifth floor.

Shoshana Hasid was diapering her infant in front of the bedroom window on the fourth floor when she saw the flash and heard the massive thud. "I saw metal and parts of bodies flying above the fourth floor," she said. "I heard screaming, women screaming 'Mommy, get me ' "

Below her balcony the bus lay ripped into twisted and blackened shards, with several broken bodies still inside. In what has become a morbidly familiar ritual, bearded Orthodox Jews scraped the wreckage, and even surrounding trees, of flesh and blood, while scores of policemen and investigators pored over the scene.

The explosion in the coastal city of Ashkelon followed about 50 minutes later, when a man dressed as an Israeli soldier joined a group of young soldiers waiting to hitch rides back to their bases after the weekend, and then detonated a bomb. Two people were killed, including the man with the bomb.

Police said the bombs were similar in construction and materials, suggesting coordinated attacks. They said the bomb in Jerusalem contained about 20 pounds of explosive, along with nails and other shrapnel material. The Ashkelon bomb was about half the size.

Though neither the Hamas statements nor the police identified the two bombers, the one in Jerusalem was suspected of being from Hebron, and the one in Ashkelon from the Gaza Strip.

These were the first suicide-bomber attacks since Aug. 21, when an explosion on a bus in Jerusalem killed four passengers and the assailant. Of the seven such attacks before that, the largest death tolls were 22 on a bus in Tel Aviv in October 1994, and 21 at a bus stop near Netanya in January 1995.

A fax sent to international news organizations, purporting to be a "military statement issued by the cells of Martyr Engineer Ayyash," declared that the bombings came as a "promise to the blood of the Engineer, who fell 50 days ago." The statement promised similar replies to other attacks against "our heroes."

At the same time, the statement contained a proposal not made by Hamas before, in effect offering a cease-fire if Israel stopped attacking Hamas and released detained members. If Israel ended its "terror activities against Hamas," it said, "we will be more cautious of every drop of blood which will be shed in the land of Palestine."

There have been reports in recent days that Hamas was discussing a similar deal with Arafat's Palestinian Authority.

There was no immediate reaction to the statement from Israel. In fact, daylong commentaries and interviews on both Israeli television channels, and on Israeli radio, made almost no mention of the purported link between the renewal of bombings and the killing of Ayyash, though a retaliatory bombing had been widely feared ever since his death. The Israeli government has never officially acknowledged that it was behind the strike, although this is generally assumed.

In private conversations with Israelis, there was a sense that to acknowledge publicly a cause-and-effect relationship between the killing of Ayyash and the bus bombings would be to suggest a justification for the terrible carnage at a time when the Jewish nation was suffering shock and anger.

Instead, most Israeli discussion on television and radio focused on whether Peres was wrong to lift a closing off of Palestinian territories Friday after 11 days, and whether Arafat was doing enough against Hamas in areas under his control.

That closing, under which Palestinians were prevented from leaving the West Bank and Gaza Strip, was ordered Feb. 12 after the Israeli government reported receiving intelligence information of an impending attack. It was lifted Friday after strong complaints from the Palestinians and their Israeli employers.

Both questions, the end of the closing and Arafat's effectiveness with Hamas, were certain to become major issues in the Israeli political campaign.

In the immediate aftermath of the tragedy, Peres' challenger for prime minister, Benjamin Netanyahu of the Likud Party, declared that "a day of mourning is not a day for political debate."

But he added, "Believe me, I think that you know that we will have a lot of time in the coming days and months to argue over the way to achieve peace with security."

Netanyahu also ordered members of his party not to organize anti-government protests of the kind that have followed past bombings.

Still, dozens of demonstrators jeered from the scaffolding of a nearby construction site when Peres, hemmed in by dozens of security men, arrived at the site of the Jerusalem bombing. "With blood and fire we'll get rid of Peres," they chanted, echoing a slogan used by Palestinians. "With blood and fire we'll win Jerusalem."

In the evening, a few score protesters milled about at the bombing site.

Netanyahu's efforts to keep the bombings out of election politics, at least Sunday, reflected his sensitivity to the accusations of anti-government "incitement," which were leveled at him after the assassination of Rabin, and again by Peres last week when Netanyahu accused the prime minister of planning to divide Jerusalem.

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PHOTO

(1 -- color) Israeli Prime Minister Shimon Peres says the peace process will continue. (2 -- color) Soldiers examine a bus destroyed by a bomb Sunday in downtown Jerusalem. (3 -- color) In Gaza, PLO leader Yasser Arafat expresses his condolences to the families of the victims of Sunday's suicide bombings in Israel. Associated Press