A Palestinian militant leader warned of new attacks as a month of relative calm ended with the slaying of four Israelis at a Sabbath dinner in the West Bank and a car explosion in the heart of Jerusalem's pub district.
"The march of martyrs will move forward," the founder of the militant group Hamas, Sheik Ahmed Yassin, told 30,000 supporters at a Gaza City rally. "Resistance will move forward."
His speech at a soccer stadium Friday came hours before the Jerusalem car bomb and the fatal shooting of four students in the West Bank settlement of Otniel.
The Jerusalem bomb, close to a bar frequented by young Americans, was an unsophisticated device that burned half the car without hurting people nearby. Police arrested a Palestinian suspect as he fled from the scene.
In the Otniel attack, two Palestinians armed with assault rifles burst into the settlement and sprayed several clips of ammunition at Jewish seminary students gathered for a Sabbath dinner in a communal dining hall.
Four Israelis died and eight were killed in the mayhem, the army said. The assailants dressed in Israeli army uniforms and used M-16 rifles -- the standard weapon of Israeli infantry units.
The gunmen sneaked into the kitchen of the settlement's seminary and killed the four students as they helped prepare the Sabbath meal, then burst into the crowded dining hall, firing in all directions, a military spokesman said.
Troops shot and killed one attacker behind a nearby building as he tried to escape, the spokesman said. Soldiers killed the other gunman after chasing him through surrounding hills.
The militant group Islamic Jihad claimed responsibility for the Otniel attack, saying it was avenging the killing of one of its West Bank militia leaders by Israeli soldiers a day earlier.
Israeli radio said there were fears that militant groups would increase attacks in the run-up to Israel's Jan. 28 general elections and an expected U.S. offensive against Iraq.
Friday's rampage ended a relative lull. There had been no shootings and bombings in Israel in the past month, though a rabbi was killed last week in a Palestinian roadside ambush in Gaza.
Hamas vowed more attacks. "Jihad will continue, and martyrdom operations (homicide attacks) will continue until the full liberation of Palestine," Sheik Yassin said at the rally.
An official in Prime Minister Ariel Sharon's office said the rally gave the green light for more violence.
"It's no coincidence that this terror infiltration was preceded by a terror rally in Gaza," the official, David Baker said. "The results of that rally were felt in Otniel."
The rally marked the 15th anniversary of Hamas' founding. Since 1987, Hamas has carried out scores of bombings that have killed hundreds of Israelis.
Hamas has been sending mixed signals in recent weeks regarding its fight against Israel.
The group's leaders have said publicly that Hamas would not change tactics.
However, a source close to truce talks told The Associated Press this week that both Hamas and Islamic Jihad promised Egyptian mediators they would to halt attacks in Israel proper. Several officials in Yasser Arafat's Fatah movement also said the militants were sending conciliatory signals.
Israel's massive military presence in the West Bank -- troops control all but one major population center -- has made it increasingly difficult for militias to operate.