Israel Alarmed, Will Crack Down on Arab Militants : Violence: Measures in occupied territories, prompted by wave of attacks, may include new detentions.

The Israeli government, alarmed by mounting casualties its forces are suffering in clashes with Palestinian guerrillas, is preparing to crack down hard on the militant Islamic movements in the occupied West Bank and Gaza Strip, senior officials said Wednesday.

Not certain that the detention of more than 1,300 suspected Islamic activists in the past three days will even reduce attacks on Israeli forces, the Cabinet discussed tougher measures at a special session Wednesday in the wake of the abduction and killing of a member of the border police.

“We are going to look around to find the most severe steps that Israeli law allows us to use to reduce . . . the operating effectiveness of Hamas and Islamic Jihad,” a senior Israel defense official said, citing the two militant Islamic groups whose attacks have inflicted heavy casualties recently and put troops on the defensive.

Early today, Israeli military commanders issued orders to deport about 418 of the detained Palestinian activists. But some of the activists’ lawyers obtained a temporary restraining order to permit a court hearing this afternoon on the orders and the Cabinet decision authorizing the action. The deportations, which would be for a period of two years, would be on an unprecedented scale.

Among the other actions under consideration were new detentions of political activists, demolition of their homes and businesses and other controversial measures Israel used against the intifada, the Palestinian rebellion against the Israeli occupation.

Israeli military authorities are also considering revision of the “rules of engagement,” which cover questions such as when a soldier may open fire, to provide greater latitude for troops in using their weapons.

“From a legal point of view, some steps may be interpreted by some foreign observers as inappropriate,” the senior defense official said, bracing for the international protests Israel expects. “But looking at the content of the steps, they may be seen as reasonable and as serving a justifiable cause.”

While the moves will be taken in the name of increased Israeli security, officials said that the underlying goals are the preservation of the peace negotiations with the Palestinians and Israel’s Arab neighbors and the enhancement of the Palestine Liberation Organization as a moderate advocate of the Palestinian cause by eliminating Hamas, its main rival.

The attacks by Hamas, which killed four Israeli soldiers in ambushes as well as the sergeant-major from the border police, have underscored the urgency for the government of Prime Minister Yitzhak Rabin in reaching agreement on Palestinian autonomy for the West Bank and Gaza Strip.

Uzi Baram, the tourism minister, said after the Cabinet meeting that Israel must negotiate directly with the PLO to isolate Hamas. Israel now meets only Palestinian residents from the West Bank and Gaza Strip, although they report back to the PLO.

Cutting the PLO out of the peace process, Baram added, has only “helped the emergence of Hamas,” which has emerged as the principal rival to the PLO’s mainstream group, Fatah, led by Yasser Arafat, the PLO chairman.

Tel Aviv Mayor Shlomo Lahat, a member of the right-wing Likud Party but a political maverick, said bluntly, “There is no substitute for the PLO, even if we don’t like it.”

The Rabin government believes it can handle the crackdown, officials said, so that Palestinian moderates get a political boost and, thus, can negotiate without fear of challenge from the Islamic movements. But officials acknowledge that the double-edged maneuver could also fail, leaving the militants as heroes of Palestinian politics and the moderates discredited.

Overall, the Cabinet reaffirmed the twin role of the security forces of containing and quelling the current unrest and with “creating the space,” as a senior official put it, for peace negotiations to proceed and for the government to make its long-term decisions free from immediate security concerns.

“We are not retreating from our commitment to a political resolution, but we cannot continue to sustain this level of casualties and to see our partners at the negotiating table undercut,” the official commented. “There will have to be some heavy blows, but they will be blows for peace.”

The Israeli human rights group B’Tselem appealed to Rabin on Wednesday not to impose collective punishment, such as prolonged curfews or demolition of suspects’ family homes. It also urged him not to expel Palestinians.

Military authorities sealed the occupied territories late Sunday when security forces began the hunt for Sgt. Major Nissim Toledano, abducted in the central Israeli city of Lod, and his Hamas captors. They have also placed hundreds of thousands of Palestinians under curfew in the Gaza Strip after three soldiers were killed in a Hamas ambush there.

After Toledano’s body was found Tuesday, Rabin vowed to wage war “without mercy” on Hamas, which had demanded the release of its jailed leader, Sheik Ahmed Yassin, in return for the policeman but then killed him before the government responded. “The world should not be surprised if this time we’ll have to take very tough measures,” Rabin said.

In renewing the armed struggle against the Israeli occupation at a time when the Arab-Israeli negotiations are at a near-stalemate, Hamas has boosted its standing among many Palestinians.

Formed by Yassin in late 1987 in Gaza as a militant offshoot of the Muslim Brotherhood, a pan-Islamic movement, Hamas asserts that the land of Palestine is sacred to Muslims and that Israel should be driven out. It accuses the PLO of “blasphemy” and treason for its willingness to accept an independent homeland encompassing just the West Bank and Gaza Strip.