Three children were injured as Israeli aircraft carried out a series of missile attacks across the Palestinian territory.
Israel on Friday also threatened new widescale military attacks against the Gaza Strip after a string of air strikes.
The three children, aged two, four and 11, were hit by flying glass in a raid on the Sabra district, in the western part of Gaza City, said Moawiya Hassanein, head of the Palestinian emergency services in Gaza.
Hassanein said, identified the children as: one-year-old Malak Mas'ad Al-Arabid, her four-year-old brother Sa'd, and cousin Abdul Rahman Sarsur, 11.
In other areas, Hassanein said, “only material damage” had resulted from the strikes. In accordance with an emergency plan developed for renewed Israeli attacks, ambulances were mobilized throughout Gaza in anticipation of casualties.
Israel's deputy prime minister, Silvan Shalom, said, that the military would soon launch a new offensive on the Hamas-ruled Gaza Strip unless the rocket fire was halted.
"If this rocket fire against Israel does not stop, it seems we will have to raise the level of our activity and step up our actions against Hamas," Shalom told public radio.
Palestinians across the coastal enclave said dozens of Israeli aircraft were spotted overhead.
Three Israeli air strikes targeted an area west of Khan Yunis, in the southern part of the Palestinian territory controlled by Hamas. Two of the missiles hit a guard post of Hamas's armed wing, the Ezzedine Al-Qassam Brigades.
A fourth raid destroyed a workshop in the refugee camp of Nusseirat, in central Gaza.
In two other air raids, Israelis targeted points in the west of Gaza City, completely destroying a small dairy factory in the Sabra district, said witnesses.
The attacks were carried out by F16 fighters, the witnesses said.
The Israeli military said it had targeted weapons manufacturing and storage facilities in the central Gaza Strip, in Gaza City in the north and the southern Gaza Strip, all in response to rockets fired from the territory.
There was no claim of responsibility for Thursday's lone rocket, which caused no casualties, but the Israeli army had said in its earlier statement that it held Hamas, the Palestinian faction which controls Gaza, "solely responsible for maintaining peace and quiet in and around" the territory.
However, the head of the Hamas movement's government in the Gaza Strip, Ismail Haniya, reacted to Israel for the increase in tensions.
"We call on the international community to intervene to stop this escalation and Israeli aggression," Haniya said in a statement.
Israel killed some 1,500 Palestinians, most of them children and women and 13 Israelis were killed in the offensive, mostly soldiers.