New strikes on Sunday leveled homes in Gaza, burying residents under the rubble as rescuers frantically dug for survivors. In all, 57 Palestinians have been killed, including 24 civilians, and more than 400 civilians have been wounded, medics say.

Israel launched the operation last Wednesday by assassinating Hamas’ military chief and carrying out dozens of airstrikes on rocket launchers and weapons storage sites in response to mounting rocket attacks. Over the weekend, the operation began to target Hamas government installations as well, including the offices of its prime minister.

Israel blames Hamas for civilian casualties, saying the group uses residential areas for cover and puts civilians in danger. It also accuses Hamas of intentionally targeting Israeli civilians with its rocket fire. Three Israelis, all civilians, have died in the fighting, and rocket attacks on Israeli cities continued interrupted Sunday.

A strike Sunday on a three-story home in the northern Gaza town of Beit Lahiya killed a 3-year-old girl and a 5-year-old boy from the same family. Hamas security officials said three missiles struck the house, owned by a family that has members who are involved in militants’ rocket squads. It was not known if any militants were in or near the house at the time of the strike.

A strike in Gaza City flattened the home of a family known for its support for Hamas, killing three women and a fourth civilian, according to Gaza health official Ashraf al-Kidra.

Another strike in the city brought down a home near a Hamas police station in the Tufah neighborhood. Rescue workers pulled out the body of a dead woman, along with several surviving members of her family.

In the Shati refugee camp near Gaza City, a missile struck the car of a Hamas militant outside his home, killing him and an 11-year-old girl passing by at the time, al-Kidra said.

Hamas security officials said most of the other houses of Hamas field operatives targeted Sunday were empty, causing no injuries

Israel’s chief military spokesman. Brig. Gen. Yoav Mordechai, said the military had been ordered to go after Hamas commanders Sunday, in addition to rocket squads, in “more targeted, more surgical and more deadly” attacks.

“I imagine in the next few hours, we will see ongoing targeted attacks on gunmen and Hamas commanders,” Mordechai told Army Radio. “More targeted, more surgical and more deadly.”

The strikes on the media centers hit two high-rise buildings, damaging the top floor offices of the Hamas TV station, Al Aqsa, and a Lebanese-based broadcaster, Al Quds TV, seen as sympathetic to the Islamists. Six Palestinian journalists were wounded, including one who lost a leg, a Gaza press association said. Foreign broadcasters, including British, German and Italian TV outlets, also had offices in the high-rises.

Two missiles made a direct hit on Al Aqsa TV’s 15th floor offices, said Bassem Madhoun, an employee of Dubai TV, which has offices in the same building.

Building windows were blown out and glass shards and debris were scattered on the street below. Some of the journalists who had been inside the building at the time took cover in the entrance hallway.

Lt. Col. Avital Leibovich, an Israeli military spokeswoman, said the strikes targeted Hamas communications equipment on the buildings’ rooftops. She accused the group of using journalists as “human shields,” and urged journalists to stay clear of Hamas bases and facilities.

Leibovich said the military has identified “hundreds” of additional targets as it pressed forward. She acknowledged that civilians were in danger, but said that Gaza militant groups bore the blame.

“One of the strategies of Hamas, not only Hamas, but Islamic Jihad as well, is locating large amounts of munitions underneath civilian homes. Many times this is the reason for this big damage or collateral damage,” she said.

The repeated militant rocket fire on Tel Aviv and Friday’s attack toward Jerusalem have significantly escalated the hostilities by widening the militants’ rocket range and putting 3.5 million Israelis, or half the country’s population, within reach. The attempt to strike Jerusalem also has symbolic resonance because both Israel and the Palestinians claim the holy city for a capital.

Israeli radio stations repeatedly interrupted their broadcasts to air “Code Red” alerts warning of impending rocket strikes.

The southern city of Beersheba was unusually quiet Sunday, with streets empty and schools closed. The city’s main shopping mall was nearly empty, but still the busiest it has been since the fighting began, shopkeepers said.

One shopper used an application on her iPhone that tracks air-raid sirens across the country. The mall, like other public places, has shelters for shoppers to run into.

With fighting showing no signs of slowing, international attempts to broker a ceasefire continued.

Nabil Shaath, an aide to Palestinian President Mahmoud Abbas who was in Cairo, confirmed that the Israeli envoy had arrived in Egypt for talks, saying there are “serious attempts to reach a ceasefire.” There was no immediate Israeli confirmation.

Hamas’ prime minister, Ismail Haniyeh, spoke to Egyptian President Mohammed Morsi. He told the Egyptian leader he supports such efforts, provided Hamas receives “guarantees that will prevent any future aggression” by Israel, his office said in a statement.

Morsi over the weekend hosted talks with Hamas’ supreme leader, as well as leaders from Hamas allies Turkey and Qatar. He also held contacts with Western leaders.

French Foreign Minister Laurent Fabius visited Israel on Sunday to offer his country’s help toward forging an “immediate ceasefire,” the French government said.

Meeting with Fabius, Israeli Foreign Minister Avigdor Lieberman thanked him for “France’s efforts to prevent casualties” but said “the moment that all the terror organizations announce a ceasefire, we can consider all the ideas that French foreign minister and other friends are raising.”

—

Aron Heller contributed reporting from Beersheba.