Guerrillas Kill 2 Israeli Merchants and 2 Arabs in Gaza : Mideast: Rivals Hamas and Fatah say they joined in attack. They cite Israeli killing of 10 of their comrades.

Two Israeli vegetable dealers were shot to death Sunday by Palestinian guerrillas in the occupied Gaza Strip as they bargained for cheap produce with two Arab middlemen who were also slain in the attack, according to Israeli military authorities.

The four men were negotiating the price of the vegetables, which in the Gaza Strip is often less than half the cost of those grown in Israel, when three guerrillas pulled up in a car around noon and sprayed them with automatic-rifle fire.

The gunmen then shot each of the four in the head to make sure they were dead, witnesses told army investigators; one guerrilla calmly plucked the Israelis’ identity cards out of their pockets.

“All of them were killed instantly,” Dr. Gerry Bassin, a physician in a nearby Israeli settlement, said after examining the bodies. “The (terrorists) are well-trained now--they know how to kill a person. In a word, this could be called a cold-blooded slaughter.”

The Islamic Resistance Movement, known as Hamas, and Fatah, the largest group within the Palestine Liberation Organization, said in leaflets left at the scene and distributed later in nearby Khan Yunis that their guerrilla units, normally bitter rivals, carried out the attack together in reprisal for the killing of 10 of their members in three recent army operations.

“We promise that (Israeli Prime Minister Yitzhak) Rabin will taste from the same cup as the mothers of our martyrs,” the leaflets declared. They also accused the victims of “stealing the products of our land.”

Later Sunday, Israeli troops shot and killed a Palestinian toddler and a boy during clashes with stone-throwing youths at two Gaza refugee camps, according to Gaza journalists.

A military spokesman confirmed the death of Faris Mohammed Kurdi, 18 months old, at the Jabaliya camp in the north of the Gaza Strip. Local doctors put the number of wounded there Sunday at 27.

The toddler was standing by the entrance to his father’s shop when he was shot in the chest by soldiers firing at fleeing teen-agers, according to local journalists. The soldiers were chasing two masked youths accused of painting political slogans on a wall when other camp residents began to stone them.

Mohammed Ghol, 11, was fatally shot during disturbances at the Shati refugee camp, according to Palestinian journalists; 11 other youths were said to have been wounded. The army said it was checking the report.

Violence has surged in the Gaza Strip during the past week. Soldiers have shot dead 10 Palestinians and wounded nearly 200, including 51 Saturday, according to military spokesmen. Palestinians have injured nine Israeli soldiers in two hand-grenade attacks on army observation posts.

Although Gaza has long been a hotbed of unrest because of its poverty and difficult living conditions in the crowded refugee camps, tension has increased since the army sealed it off March 31 after attacks in which 15 Israeli civilians, soldiers and police were killed, largely in Gaza or by Gazans. Since then, the two vegetable dealers and one other Israeli, a lawyer working with Palestinians in Gaza on economic development of the region, have been killed.

Sunday’s attack on the vegetable dealers, one of the bloodiest this year, seemed likely to fuel demands among Israelis to pull their troops and 5,000 settlers out of Gaza, either in an agreement with the Palestinian residents there or even unilaterally. Right-wing politicians, however, renewed their calls for harsher measures, including imposition of the death penalty.

The Israelis killed Sunday were identified as Nissim Palas, 38, from Dimona in the Negev Desert, and Avshalom Harfon, 21, a recently discharged soldier from nearby Ofakim. The Palestinians were Jad abu Zhurab, 25, from Hebron on the occupied West Bank, and Tewfik Zhurab, 19, from Khan Yunis in southern Gaza.

The killings brought a plea from Rabin to Israelis “not to throw their lives away” and to stay out of the Gaza Strip, even if accompanied by local Palestinian residents. The risk is not worth the money to be gained by buying cheap agricultural produce there, he said.

Israeli settlers in the region said that fewer vegetable dealers had come in recent weeks and that army patrols have been chasing away those who did.

Yet, the hefty profits continued to draw some to the informal market near the Israeli settlement of Gadid outside Khan Yunis.

“There are always those for whom the temptation proves too great,” said Eitan Hadari, the security officer at Ganei Tal, another nearby Israeli settlement, lamenting that people would risk their lives “for a handful of shekels.”