Palestinian militants fired 22 mortar shells from the Gaza Strip overnight Thursday and early morning Friday, as the Israel Defense Forces continued its preparations for military action in Gaza.

The mortars struck the Western Negev, damaging one building. No one was hurt in any of the incidents.

Reportedly, a "limited operation" will begin within days that will combine an air attack with some ground operations against Hamas and other Gaza terror groups.

The cabinet has given the go-ahead for an operation of a few days' duration with clearly defined goals.

Meanwhile, Israel renewed its transfer of humanitarian aid into the Gaza Strip on Friday.

The IDF said the first of approximately 90 trucks had started to deliver medicine, fuel, cooking gas and other vital goods into Gaza. The shipment includes a large donation of goods from Egyptian President Hosni Mubarak's wife.

On Sunday, the prime minister will hold a series of consultations ahead of a possible military action in the Strip. No major move will apparently be made until these discussions have concluded.

In statements Thursday, senior security officials were unwavering. "Anyone who harms Israeli citizens and soldiers will pay the price," Defense Minister Ehud Barak said.

IDF Chief of Staff Gabi Ashkenazi, speaking at the graduation of a pilots' training course at Hazerim Air Force Base, said, "We will have to use all of our might against the terror infrastructure and create a different security reality around the Gaza Strip."

Israel is planning a relatively short operation that will cause maximum damage to Hamas "assets." The defense establishment says the operation would not necessarily limit itself to stopping rocket launches and that during the operation, daily massive rocket launches can be expected. Hamas might fire rockets with a range beyond the 20 kilometers it has used so far.

By evening Thursday, seven rockets and nine mortars had been fired from the Gaza Strip, as opposed to 70 mortars and rockets shot the day before. One Grad rocket landed south of Ashkelon. There were no injuries or damage.

Despite the rockets, Barak opened the crossings this morning for the passage of food and medicine. Although Hamas operatives are behind most of the rocket launches, Palestinian sources in the Strip said Thursday that the Islamist group still wants to renew the cease-fire.

The sources said Hamas is under pressure by Gaza residents and other factions to significantly improve the terms of the cease-fire, particularly regarding the opening of the crossings in light of the increased distress of the civilian population.

The sources warned that an Israeli ground operation would result in many civilian casualties in Gaza, especially in the refugee camps.

Prime Minister Ehud Olmert Thursday called on Gazans to overthrow Hamas.

"We do not want to fight the Palestinian people, but we will not allow Hamas to hurt our children," Olmert said in an interview with Al-Arabiya television. He added Israel had great power but does not wish to use it.

Meanwhile, in the Gaza Strip Thursday there were long lines at bakeries, and sales were limited to NIS 3 worth of bread, less than a large family needs per day. Electrical power and water was cut several times Thursday. Cooking is difficult due to a gas shortage.

"It is impossible to live like this," a Gaza man told Haaretz. We have to come to some resolution - either a full cease-fire or full-scale fighting with Israel."

The meetings Olmert is expected to hold on Sunday will relate to three issues. The first is preparation of the home front: Olmert wants to know what reinforcement of buildings can be completed before military action is taken, and to urgently complete whatever can be completed in terms of reinforcement.

The second issue involves humanitarian aid shipments to Gaza. Olmert wants reports on stockpiles of essential items to ensure that a humanitarian crisis does not break out in the Strip during military action.

The third issue involves diplomatic moves to garner international support for military action against Hamas.

A government official in Jerusalem said there would be no moves before all necessary preparations are in place.