This article was originally published by Haaretz and is republished with permission.

A Palestinian policeman stands guard outside the destroyed Hamas-run Interior Ministry building in Gaza City, after a barrage of Israeli air strikes hit the Gaza Strip in recent days. (Wissam Nassar, Maan Images)

At least 61 Palestinians have been killed, among them at least 29 civilians, in an ongoing IDF ground incursion near the northern Gaza Strip town of Jabaliya on Saturday.

Believed to be among the dead civilians is a 17-year-old girl and her 16-year-old brother, a 45-year-old man and his 20-year-old son, and two sisters thought to be in their early 20s.

The remaining Palestinians killed were members of Hamas and Islamic Jihad.

The sisters and another civilian were killed by tank shells that struck two houses in separate attacks, Palestinian officials said. Rescue teams evacuated a 7-month-old boy from one of the houses, unharmed.

The IDF said it would look into reports of tank shells hitting houses.

Five IDF soldiers were wounded during the fighting - three of them lightly and two others who suffered light to moderate injuries. The soldiers were evacuated to Soroka Medical Center in Be'er Sheba for treatment.

Sources in Gaza report that IDF soldiers exchanged heavy gunfire with Palestinian gunmen on the eastern outskirts of Jabaliya, situated 2-3 kilometers from the fence which lies on the Israel-Gaza border.

The ground forces, which included units from Givati Brigades, the Armored Corps, and the Engineering Corps, received air support from the Israel Air Force.

IAF planes launched missiles at groups of armed Palestinians during the fighting.

Two of the dead Palestinian children have been identified as Jaqueline Abu-Shbak, 12, and her brother Iyad Abu-Shbak. The name of the third child has yet to be released.

The IDF said the incursion has become routine in recent months, and is not indicative of any change in the army's policies in the territories. The IDF added that troops have entered the strip on an average of twice a week.

Senior officials said Saturday that the increasing number of Qassams fired at the western Negev has no bearing on the continued military raids into Gaza.

Rather than making due with pinpoint strikes against rocket launchers, the army is recommending a series of steps against Hamas targets in Gaza.

Tareq Dardouna, a resident of the Jebaliya area, told The Associated Press that a relative was killed outside his home in the crossfire that began raging at 3 A.M.

"His body is still on the ground," Dardouna said in a telephone interview from his home, where he was tending to four wounded people. "Ambulances tried to come, but they came under fire. ... We are in a real war."

Witnesses said one clash erupted early Saturday when Hamas gunmen engaged IDF troops backed by helicopters that had entered the Gaza Strip.

IDF troops have been operating on the outskirts of Beit Hanun in the northern Strip since Thursday night.

At least 91 Palestinians have been killed in four days of IDF raids and air strikes in the coastal territory, launched in the wake of a massive Qassam rocket barrage on the western Negev that killed an Israeli civilian.