An Israeli civilian whose car was stoned opened fire with a submachine gun on a crowd of Moslem worshipers Friday, wounding two 8-year-old boys and six other Palestinians.

Also Friday, an Arab stabbed a Boston-born Israeli in another Palestinian city. The bleeding victim wheeled around and shot and wounded his attacker, whose trail of blood led police to his hideout. The two noontime incidents underlined the growing involvement of Israeli civilians in clashes with Palestinians amid an Arab uprising in the occupied West Bank of the Jordan River and in the Gaza Strip, in which 210 Arabs and four Israelis have been killed. Arab journalists in the West Bank city of Nablus said that a resident of a Jewish settlement in the region and his wife were stoned as they drove by the Mazuz Masri mosque after noon prayers Friday, the Moslem holy day. The settler left his car and fired his Uzi submachine gun into a group of worshipers emerging from the mosque, triggering a melee in which the Arabs hurled rocks, watermelons and even shoes, the journalists said. Arab doctors at Al Ittihad Hospital in Nablus said that eight Palestinians, including the two boys, were wounded in the arms or legs in the shooting, one of them seriously. The Israeli settler and his wife were slightly injured by the rocks, Radio Israel said. Israeli troops rushing toward the sound of gunfire then clashed with the crowd of Palestinians, firing tear gas and rubber bullets in a skirmish that Al Ittihad doctors said sent five more injured Arabs to the hospital. The Nablus clash occurred only minutes after another Israeli settler, Yonah Chaiken, 35, was stabbed twice in the back as he shopped Friday in the Arab bazaar of the southern West Bank city of Hebron. Chaiken later blamed the attack on Washington, charging that U.S. pressure on Israel to protect Palestinian human rights has encouraged Arab attacks during the seven-month old uprising, Radio Israel reported. Chaiken, one of 200 Jewish settlers in the city of 80,000 Arabs, said from his hospital bed that he was shopping in the bazaar when a young Palestinian stabbed him in the upper and lower back. Chaiken pulled a handgun, chased his attacker 50 yards and shot him in the shoulder before stumbling 300 yards to one of the buildings in the center of Hebron that house Jewish families, other Hebron settlers said. Chaiken is a Boston-born computer programmer who migrated to Israel in 1984 and has eight children.