Executions by Palestinians May Also Hurt Uprising : Occupied areas: The slayings of suspected collaborators are more than keeping pace with Arab deaths at the hands of Israeli soldiers.

Israeli-occupied West Bank Twice this year, self-appointed rebel executioners have forced a suspected collaborator into the central mosque here and made him foretell his death over a loudspeaker.

Then the victims were killed. One was hacked and slashed first; the other was beaten, kicked and trampled.

Killings such as these have become an important feature of the Palestinian uprising, known as the intifada . Now, the executioners’ weapons are competing with the stones thrown by young people as symbols of the revolt.

The slayings of Palestinians suspected of cooperating with the Israeli army and secret police--carried out in defiance of pleas by Palestinian leaders--are more than keeping pace with killings at the hands of Israeli soldiers. So far this year, 19 Palestinians have been killed by other Palestinians; 18 have been killed by soldiers.

The persistence of Palestinians killing Palestinians has raised questions about the hold the public Palestinian leadership has on grass-roots activists. Those who hope to persuade Israel to agree to a new Palestinian state have been placed on the defensive. Indeed, many Palestinians now fear that the killings may eventually undermine the uprising.

“We do not want someone taking to himself the power to decide who is participating enthusiastically in the intifada and who is not,” a Palestinian activist in Jerusalem said the other day.

Many of these executions have taken place in the occupied Gaza Strip, where Islamic fundamentalist groups sometimes strike at Palestinians believed to be involved in drug dealing and prostitution. On the West Bank, Palestinians have become alarmed about renegade groups of masked men carrying out attacks on nationalists and robbing stores and homes.

Beit Furik, an impoverished farm town near Nablus, has a long history of fighting the Israelis. In 1967, Yasser Arafat, chairman of the Palestine Liberation Organization, escaped pursuing Israeli soldiers by hiding in the basement of an old house here.

On Feb. 27, young men forced Ali Nasasra into Beit Furik’s mosque, where according to witnesses he confessed to informing on Palestinians. Nasasra had been banished from the village 20 years ago because, residents say, he worked for Shin Bet, Israel’s domestic intelligence agency.

He was found at the home of a relative and seized by about a dozen men armed with hatchets and knives. His captors, members of a Nablus-based group called Revolutionary Security, said he would be subjected to the “justice of the people.”

As Nasasra, 45, left the mosque, scores of people beat him with sticks, kicked him and trampled him to death.

In January, a group of masked youths dragged Mohammed Hatatbeh, 53, to the Beit Furik mosque, where he was forced to confess over the mosque’s sound system. He was said to have admitted to leading two Palestinian gunman into a fatal army ambush in 1969 and to cooperating with the Israelis ever since.

After confessing, Hatatbeh was released--but two days later, masked executioners came to his home, took him to a square and hacked him to death with axes. The blood-soaked ground where he died has been left undisturbed as a warning to others, youths in the village told reporters.

“The collaborator was dangerous,” one of the youths said. “He was responsible for the deaths of two of our fighters, and he continued to work for the Israelis.”

The youth, who gave his name as Najib, guided the reporters to the scene of the killing. When asked why Beit Furik rebels had disobeyed Palestinian leaders’ orders to stop killing suspected informers, he responded with a familiar refrain:

“Arafat is not here. He does not know our situation.”

Najib insisted that Hatatbeh was given a trial and that his killing was necessary in view of the risks the rebel activists take in their battle with the Israelis.

The killing of suspected collaborators began in earnest last summer. At first, Palestinian leaders and PLO members justified the deaths on grounds that the informers were placing activists in mortal danger by identifying them to the Israelis.

Over the years, according to Israeli intelligence experts, the Shin Bet recruited many informers in the West Bank and Gaza and still has thousands of them on its payroll.

Some Israeli politicians, including the hawkish Ariel Sharon, a member of Parliament, have suggested that armed collaborators be unleashed on the nationalists as a way to quell the intifada .

As the number of executions mounted, the PLO announced that it alone could authorize an execution. But the killing continued.

At least 170 Palestinians are believed to have been killed by other Palestinians since the uprising began 27 months ago, all but about 30 of them since last June.

By November, the uprising’s public leadership had become alarmed. Faisal Husseini, one of the few widely recognized voices of the uprising, went from village to village appealing for an end to the killing.

The executioners resist discipline. Said Kanaan, a Nablus businessman and longtime pro-PLO contact, recalled that last November he tried to deliver a letter containing an appeal from Arafat to a nationalist group known as the Black Panthers, responsible for slaying at least eight suspected collaborators in Nablus.

“They took the letter and asked me to prove it was authentic,” Kanaan said. “I tried to assure them, but they threw the letter up in the air and shot at it. They demanded that Arafat make a speech on radio.”

Arafat complied, but it is not clear whether his appeal succeeded in cooling their ardor.