The air force continued to hammer away at Hamas targets in the Gaza Strip on Thursday as the IDF made its first foray into northern Gaza, sending tanks and infantry to take over Kassam launch sites.

At least eight Palestinians died in the Israeli attacks, including a Hamas operative who was killed when the IAF dropped a bomb on a two-story building belonging to Hamas's Executive Force. Forty-five others were wounded in the bombing, which leveled the building and several next to it.

Three people were killed later in the day when IAF helicopters fired a missile at a vehicle in southern Gaza that the IDF said was transporting a Kassam rocket squad. Hamas operatives said they had fired three rockets from that area shortly before the air strike.

Palestinians also reported an additional three killed IAF aircraft fired on Hamas operatives late Thursday night.

The air strikes were deemed successful by the IDF, with senior officers claiming they were impairing Hamas's ability to fire rockets despite the fact that more than 20 had been launched throughout day.

Meanwhile, tanks and infantry rolled into the Gaza Strip just north of Beit Lahiya, a popular Kassam launch pad. A small infantry force traveling in armored personnel carriers also entered the Strip.

Southern Command sources said the tanks only penetrated 400 meters into Gaza, near the former settlement of Dugit, to conduct surveillance of areas used to fire rockets into Sderot, and were not part of a large-scale or deep incursion.

Military sources said the operation was designed to take control of areas from where Kassams were being fired, in an effort to reduce rocket attacks on Sderot.

Later in the day, the IDF began deploying large numbers of artillery and armored personnel carriers around the Gaza Strip, for the first time in six months.

Palestinian sources claimed the IDF had electronically taken over the frequencies of several Gaza radio stations, using them to call on civilians to flee areas from where Kassams were launched.

"All of our operations are intended to minimize the Kassam fire," Defense Minister Amir Peretz told a radio station in the South. "The ground incursion also has a goal - to take over areas from which we can deal with and warn of rocket fire as it happens."

Early Thursday morning, IAF missiles hit a vehicle traveling in Gaza City's Sheikh Radwan neighborhood. Two people were killed and four were wounded, including Imad Shabanah, the commander of a Hamas rocket manufacturing cell.

Hamas spokesman Abu Obaida said in response to the air strike that "the Zionist enemy has declared war" and that the terror group reserved the right to respond to the attack, even with suicide bombings.

Fawzi Barhoum, a Hamas spokesman, said Hamas's opponents are "pro-Zionist and pro-American elements who are working in a systematic, barbaric pre-planned campaign against Hamas and its elected leadership."

Military sources said that the IDF planned to continue striking from the air at Hamas targets. The military buildup around Gaza, one source said, was meant to prepare for the possibility that the situation would escalate. On Sunday, the security cabinet is scheduled to convene to hear briefings from the IDF on the Gaza situation and to determine the type of operation.

"We plan to be prepared for all possibilities," the military source said. "If Hamas escalates the situation on their side, then we might need to escalate the situation on our side."

Meanwhile, the Home Front Command issued orders to the Ashkelon Municipality on Thursday ahead of the possibility that rockets would begin landing in the coastal city.

On Thursday, over 20 rockets slammed into Sderot, one of which hit a classroom, lightly wounding two pupils. Later in the day, a rocket struck a factory in Sderot, sparking a fire that firefighters worked frantically to extinguish. No casualties were reported.

Another rocket landed in one of the kibbutzim in the area, injuring animals in the kibbutz petting zoo and causing damage.

AP contributed to this report

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