Israeli military officials said Hamas fired three mortar shells from Gaza hours after a humanitarian cease-fire went into effect Thursday.
Rockets were launched into southern Israel at noon local time, causing no injuries, Israeli police spokesman Micky Rosenfeld said.
There was no immediate reaction from Hamas, whose armed wing Qassam Brigades has been behind many of the rocket attacks toward Israel.
Israel and Hamas had begun observing a five-hour humanitarian cease-fire, as fighting extended into a 10th day.
The two sides agreed to the pause following a request by the United Nations so that supplies could be delivered to Gaza. Despite the call to lay down arms, Israeli military personnel told Al Jazeera that the probability of a ground offensive in Gaza is "increasing."
Israel has activated 40,000 troops and currently has approval for another 8,000, said the military official, who spoke on condition of anonymity.
In 2012, during the last Israeli campaign in Gaza, the military called up 70,000 troops but did not invade.
Fighting continued in the lead-up to the start of the cease-fire Thursday at 10 a.m local time. Police in the southern Gaza town of Rafah said tank shells landed on a house, killing at least three civilians.
The Israeli military said 15 rockets were fired into Israel Thursday morning. It also said it prevented an attack by 13 fighters who infiltrated into Israel through a tunnel from Gaza.
The cross-border fighting has so far killed more than 220 Palestinians and one Israeli, according to officials.
Robert Serry, the U.N. special coordinator for the Middle East peace process, had asked Israel to agree to the "unilateral humanitarian pause" so that supplies can be delivered to Gaza, U.N. deputy spokesman Farhan Haq told The Associated Press. Serry will "urge the parties in Gaza to respect that pause," Haq said.
The humanitarian pause came after Israel intensified airstrikes overnight on Wednesday, as it promised to ramp up its offensive and ordered some 100,000 Palestinians to evacuate their homes ahead of more strikes.
Four Palestinian children were killed on a Gaza beach and one critically wounded when Israel's naval gunboats shelled the area Wednesday, according to journalists and medics at the scene.
"The kids were playing football on the beach. They were all ... under the age of 15," Ahmed Abu Hassera, 22, told Reuters.
"When the first shell hit the land, they ran but another shell hit them all ... It looked as if the shells were chasing them," Hassera, whose shirt was stained with blood, said.
Ashraf al-Qidra, spokesman for the Gaza Health Ministry called it a "cowardly crime."
Armed groups in Gaza resumed fire Wednesday morning after a relatively quiet night. Israel’s military said 1,215 rockets have been fired from Gaza, with only 38 exploding in built-up areas, Haaretz reported. Over 200 of the mortars have been intercepted by Israel’s Iron Dome missile defense system, for which a U.S. Senate panel on Tuesday approved a 50 percent funding boost, Maan reported.
Israel has launched more than 1,825 airstrikes on the densely populated Gaza Strip, killing many civilians. Of the 214 Palestinians killed so far in Operation Protective Edge, at least 67 were women and children and 11 were elderly, according to Ashraf al-Qedra, spokesman for the Gaza Health Ministry. Over 1,500 have been injured, and Gaza hospitals have reported severe medical-supply shortages.
The first Israeli death was reported Tuesday, after shrapnel from a mortar hit a civilian handing out food to soldiers near the Gaza border.
Rocket barrages from Gaza over the past week have also hit several sectors of the Jewish state’s economy, including manufacturing, retail, advertising and tourism, Haaretz reported.
Netanyahu’s coalition has faced political troubles since the recent Gaza clashes. On Tuesday, the prime minister fired Deputy Defense Minister Danny Danon, who had called Netanyahu a “failure” and said that Hamas was controlling the conflict, Maan reported.
“It is inconceivable that the deputy defense minister will attack the country’s leadership leading this campaign,” a statement by Netanyahu said, according to Maan. “The severe remarks show a lack of responsibility … and even are used by Hamas terror group to slam the government.”
Earlier, Israel’s foreign minister, Avigdor Lieberman, faulted Netanyahu for accepting the Egyptian truce, saying Israel should re-conquer Gaza. Lieberman had threatened to pull out of Netanyahu’s coalition before the offensive started — which could threaten the government — saying the prime minister was not being tough enough on Hamas.
After the failed cease-fire attempt Tuesday, Palestinian President Mahmoud Abbas will meet with the Egyptian foreign minister Wednesday and President Abdel Fattah El Sisi Thursday morning.
With wire services