JERUSALEM (AP) – Prime Minister Ariel Sharon said Sunday there would be no holds barred in stopping Palestinian violence that has heated up ahead of Israel’s planned pullout from the Gaza Strip.

Defense Minister Shaul Mofaz, speaking at a weekly Cabinet meeting, said Israel would launch a “massive, prolonged and intricate” military strike if the Palestinian Authority doesn’t curb militants who have been barraging Israeli targets with rockets and mortar rounds in recent days, a meeting participant said.

Thousands of Israeli troops massed along the Gaza border, meanwhile, in preparation for a possible ground offensive. Israel Radio reported that Lt. Gen. Dan Halutz told Sharon’s ministers that preparations for the strike are complete.

Palestinian police, meanwhile, began removing Hamas, Islamic Jihad and Fatah flags from the streets of Gaza early Sunday, leaving only the Palestinian national flag. On Saturday, Palestinian leader Mahmoud Abbas said he would brook no challenges to his government’s authority, and called on militants to stop their attacks.

Palestinian militants have fired more than 100 projectiles at Israeli targets since Thursday, in one of the heaviest onslaughts since the two sides declared a now-moribund truce in February.

The violence cast a heavy pall over Israel’s planned withdrawal from Gaza and northern West Bank settlements next month, and has sent international mediators scrambling to try to restore calm ahead of the pullout.

“I spoke to the heads of the defense establishment … and informed them that there are to be no restraints on our operations,” Sharon told Cabinet ministers at the start of a weekly Cabinet meeting

Israeli Deputy Defense Minister Zeev Boim told Israel Radio earlier in the day that the military would decide soon whether to launch a ground offensive before or after U.S. Secretary of State Condoleezza Rice pays a snap visit to the region this weekend to try to halt the Palestinian attacks.

Rocket and mortar attacks continued Sunday morning, with at least four homemade rockets and eight mortar rounds launched at Sderot, a town just over the border from Gaza that has been hit by more than 40 rockets since Thursday.

Also Sunday, an Israeli sniper shot and killed a senior Hamas field commander in a targeted strike after a mortar landed in the Gaza settlement of Neve Dekalim, the army and Hamas officials said.

The army plans to invade northern Gaza – the area militants use to fire rockets at Sderot – a military official said on condition of anonymity. But he said the massing of thousands of soldiers along the border is meant more as a threat for the time being. The official declined to be identified because he was discussing sensitive military plans.

Palestinian negotiator Saeb Erekat said an Israeli incursion into Gaza “will have a disastrous impact on the disengagement plan, and all efforts to make it a successful and smooth and peaceful disengagement.”

He said Abbas was committed to reining in militants, and has “zero tolerance for multiple authorities and multiple guns.”

On Saturday, Abbas appealed to militant groups to halt their attacks on Israel and recommit themselves to the truce.

“I call upon all the Palestinian factions and forces to renew and to declare their commitment to what we had agreed upon, to respect the (Palestinian) Authority … and to obey the truce,” he said. “We are not going to allow anyone to gamble with our national cause,” Abbas said in a televised address from his Gaza City office.

Mofaz postponed a trip to Washington because of the escalating violence. Mofaz was to have left for the U.S. on Saturday, but now plans to go later in the week.

While the focus Sunday was on stopping Palestinian militants, Israeli officials were also occupied with preventing Jewish extremists from disrupting next month’s pullout.

Jewish settlers must be prevented from entering Gaza in support of pullout opponents who want to sabotage the evacuation, Sharon was quoted as saying by a meeting participant.

Uri Barlev, the southern district police chief, said police would not authorize a massive march and rally this week by pullout opponents. Authorization has been withheld because protesters plan to enter Gush Katif, which was sealed last week to nonresidents for fear they would flood the area and try to sabotage the withdrawal.