JERUSALEM - Prime Minister Benjamin Netanyahu said Thursday that Israel will destroy Hamas' tunnel network in the Gaza Strip designed for deadly attacks inside Israel, "with or without a cease-fire," as the military called up another 16,000 reservists to pursue its campaign against Palestinian militants in the densely-populated territory.
Netanyahu's warning came as international efforts to end the 23-day-old conflict seemed to sputter despite concern over the mounting death toll. More than 1,422 Palestinians have been killed so far, including many civilians, according to Gaza health officials.
The high Palestinian death toll surpasses the number of Palestinians killed in Israel's last major invasion of Gaza in January 2009, when, according to Palestinian rights groups, at least 1,410 people died. Israel had said the aim of that operation was to end Palestinian rocket attacks.
At least 59 Israelis have been killed in this month's fighting, most of them soldiers - also a much higher death toll compared to the 2009 campaign.
"We have neutralized dozens of terror tunnels and we are committed to complete this mission, with or without a cease-fire," Netanyahu said. "Therefore, I will not agree to any offer that does not allow the military to complete this important mission for the security of the people of Israel."
Israel expanded what started July 8 as an aerial campaign against Hamas and widened it into a ground offensive on July 17. Since then, Israel says the campaign has concentrated on destroying cross-border tunnels militants constructed to carry out attacks inside Israeli territory and ending rocket attacks on its cities.
Israel says most of the 32 tunnels it uncovered have now been demolished and that getting rid of the remainder will take no more than a few days.
An Israeli defense official, speaking on condition of anonymity because he was not permitted to discuss the matter with media, said the purpose of the latest call-up was to provide relief for troops currently on the Gaza firing line. Thursday's call-ups were rotations, leaving the overall number of mobilized Israeli reservists at around 70,000, according to a military official, who spoke on condition of anonymity in line with regulations.
However, Israeli officials have also said they do not rule out broadening operations in the coming days.
Fifty-six Israeli soldiers and three civilians on the Israeli side have been killed since the offensive began, as Palestinians fired over 2,850 rockets at Israel - some reaching major cities but many intercepted by the Iron Dome defense system - and carried out deadly attacks through tunnels beneath the heavily guarded frontier.
One Israeli was seriously wounded Thursday when a Palestinian rocket exploded in a residential area of Kiryat Gat, the military said. The rocket damaged a house and destroyed several cars parked on the street. Another rocket was intercepted over Tel Aviv by Israel's rocket defense system, the military said.
Israel has said it launched the Gaza operation to try to end relentless rocket fire on its cities from Hamas and other armed Palestinian groups as well as to seek and destroy a network of tunnels Hamas dug to infiltrate Israel for attacks.
Israeli attacks continued Thursday, killing 43 people in the strip.
Gazans said munitions struck the Omar Ibn al-Khatab mosque next to a U.N. school in the northern town of Beit Lahiya. The office of the military spokesman said Palestinian snipers inside the mosque had shot at troops, wounding one Israeli soldier and prompting retaliatory fire.
The strike in Beit Lahiya damaged water tanks on the roof of a building near the mosque, sending shrapnel flying into the adjacent school compound, where dozens of Palestinians displaced by the fighting had taken shelter.
"The shrapnel from the strike on the mosque hit people who were in the street and at the entrance of the school," said Sami Salebi, an area resident.
Gaza health official Ashraf al-Kidra said at least 15 people were wounded, with three of them in critical condition.
Kifah Rafati, 40, was being treated for shrapnel injuries at the nearby Kamal Adwan Hospital. She said she and her six children had been sleeping in a classroom facing the mosque when the explosion went off. "There is no safety anywhere," she said.
On Wednesday, Israeli tank shells struck a U.N. school in the Jebaliya refugee camp where some 3,300 Gazans had crammed in to seek refuge from the fighting, killing at least 17 people. The military said it was responding to mortar fire coming from the area of the school.
U.N. chief Ban Ki-moon called the deadly school shelling "outrageous" and "unjustifiable," and demanded an immediate humanitarian cease-fire. "Nothing is more shameful than attacking sleeping children," Ban said.
The White House also criticized the shelling of the U.N. school in Jebaliya.
"We are extremely concerned that thousands of internally displaced Palestinians who have been called on by the Israeli military to evacuate their homes are not safe in U.N. designated shelters in Gaza," said Bernadette Meehan, a spokeswoman for the White House's National Security Council.
Also Wednesday, an Israeli airstrike hit a crowded shopping area in the Shijaiyah district in Gaza City, killing at least 16 people, including Palestinian video journalist Rami Rayan, who was wearing a press vest at the time, and wounding more than 200 people, al-Kidra said. In all, at least 116 Palestinians and three Israeli soldiers died Wednesday.
Hamas has said it will only halt fire once it receives guarantees that a Gaza border blockade by Israel and Egypt - tightened after the Islamic militant group seized power in Gaza in 2007 - will be lifted.
Israel says it wants to decimate Hamas' rocket-launching capability, diminish its weapons arsenal and demolish the tunnels. It has launched more than 4,000 strikes against Hamas-linked targets, including rocket launchers and mosques where it says weapons were being stored.
Israeli strikes have also hit dozens of homes. Mahmoud Abu Rahma of the Palestinian human rights group Al Mezan said nearly half of the Palestinians killed so far died in their homes.
Israeli officials have said Hamas uses Gaza's civilians as human shields by firing rockets from crowded neighborhoods.
However, Pierre Kraehenbuehl, chief of the U.N. aid agency for Palestinian refugees, said Israel must try harder to ensure that civilians are not hurt, especially in Gaza, where 1.7 million people are squeezed into a small coastal territory. His agency has opened 80 of its schools to more than 200,000 Palestinians fleeing the violence.
"What maybe the world forgets ... is that the people of Gaza have nowhere to go," he said. "So when the fighting starts and they move, it is not as if they can cross a border to somewhere."
Yigal Palmor, spokesman for the Israeli Foreign Ministry, called Wednesday's deaths at the U.N. school "tragic," but blamed "Hamas's criminal entrenchment within civilian populations and its frenzy to wage war within civilian establishments."
He noted that Kraehenbuehl's U.N. agency has issued three statements about finding weapons in empty schools, presumably stashed there by militants.