Overnight, Israeli jets target several buildings and a mosque in Gaza. Residents of Gaza flee their homes and take refuge in the U.N.-run schools. (Reuters)

Overnight, Israeli jets target several buildings and a mosque in Gaza. Residents of Gaza flee their homes and take refuge in the U.N.-run schools. (Reuters)

Israeli commandos made a first ground incursion into the Gaza Strip early Sunday and knocked out Hamas rocket-launching sites. In a brief fire fight with Hamas militants, four Israeli soldiers were lightly wounded in the dawn raid but returned safely to Israel.

Signaling a potential increase in operations targeting the sites, Israel dropped thousands of leaflets from the sky and issued warnings by recorded telephone message, telling residents of the northern Gaza Strip that they had until noon to leave their homes and head south.

On Saturday evening, streets in the northern communities of the coastal enclave were empty of foot and vehicle traffic. Locals who remained behind said as many as two-thirds of the population had cleared out.

Those who stayed behind, such as a group of men at an area mosque, remained defiant. “Let the Israelis come,” they shouted. The Hamas government urged Gaza residents to remain in their homes.

The Israel Defense Forces’ leaflets told residents of east of Al-Attara to head south quickly: “The IDF operation will be temporary and short. Those who do not adhere to these directives will jeopardize their own lives and the lives of their families. Be careful, stay safe.”

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It was unclear whether the Israelis were signaling an imminent ground assault or heavier bombing. There are three brigades poised along the Gaza frontier, including armor, tanks and combat bulldozers. About 20,000 reservists have been activated.

In its five-day campaign, Israel has struck more than 1,320 sites in Gaza, including weapons caches, tunnels and launch pads. They have also hit hundreds of homes in strikes that seek to kill a Hamas or Islamic Jihad militant or to destroy what Israelis describe as command and control centers.

The Gaza death toll has passed 170, with more than 1,000 wounded, including many women and children. On Saturday, Israeli aircraft hit a home for the disabled, killing two wheelchair-bound residents. Israeli military spokesman Lt. Col. Peter Lerner called the result “clearly tragic” and said it would be investigated.

In another major attack Saturday evening, an Israeli warplane destroyed the home of Gaza Police Chief Tayseer al-Batsh and damaged a nearby mosque. Gaza health officials said at least 18 people were killed, making it the single deadliest strike.

Israel Defense Forces released footage showing targeting and destruction of Gaza rocket launcher that was firing rockets toward Tel Aviv on Sunday. (YouTube/idfnadesk)

The Israeli military reports that 802 rockets had been fired at Israel since operations began Tuesday. Air-raid sirens have sounded over Israel’s major cities, including Haifa, Tel Aviv and Jerusalem. Scores of Israelis have been treated for shock and minor injuries.