GAZA CITY, Gaza Strip (AP) -- Israeli aircraft fired two missiles at a 12-story apartment tower in downtown Gaza City on Saturday, collapsing the building, sending a huge fireball into the sky and wounding at least 22 people, including 11 children, witnesses and Palestinian officials said.
Israel has launched some 5,000 airstrikes against Gaza in nearly seven weeks of fighting with Hamas, but Saturday's strike marked the first time an entire high-rise was toppled. The explosion shook nearby buildings.
The Israeli military said the airstrike targeted a Hamas operations room in the building, but did not explain why the entire tower with 48 apartments was levelled.
Gaza police say Israeli aircraft fired a warning missile at the roof of the tower at dusk, followed five minutes later by two missiles with explosives.
Ayman Sahabani, the head of the emergency room at Gaza City's Shifa Hospital, said at least 22 people were wounded, including 11 children and five women.
The leveling of the tower was a further sign of escalation following a breakdown of Egyptian-brokered cease-fire talks and the collapse of a temporary truce earlier this week.
The military said Gaza militants fired at least 93 rockets and mortar shells at Israel on Saturday. The barrage came a day after a mortar shell from Gaza hit a farming village in southern Israel on Friday, killing a 4-year-old boy.
Israeli media said large numbers of residents of southern Israeli communities near the Gaza border were leaving their homes and heading for safer areas following the death of the boy in Kibbutz Nahal Oz.
"I say whoever can leave, whose presence is not crucial should leave," said Minister of Public Security Yitzhak Ahronovich during a visit to the south on Saturday.
Defense Minister Moshe Yaalon called on southern residents to be ready for a prolonged campaign against Hamas militants.
"In the end we will win," he said Saturday. "This is a test of staying power and strength."
Meanwhile, the Egyptian Foreign Ministry urged Israel and Hamas to resume indirect talks and agree to an open-ended cease-fire.
The appeal came Saturday after Western-backed Palestinian President Mahmoud Abbas met with Egyptian President Abdel-Fattah el-Sissi in Cairo. Egyptian officials did not say how they expected renewed talks to produce a different outcome after repeated failures.
Israeli government spokesman Mark Regev had no immediate comment regarding the renewed call for a cease-fire. Sami Abu Zuhri, a spokesman for Gaza's ruling Hamas, said the group would consider the Egyptian appeal, but there was no sign it would budge from longstanding demands.
Also Saturday, senior Hamas officials said the group has signed a pledge to back any Palestinian bid to join the International Criminal Court.
Such written consent increases already strong domestic pressure on Abbas to take such a step. Palestinian acceptance of the court's jurisdiction could expose Israel - as well as Hamas - to war crimes investigations.
The Egyptian-brokered talks and a temporary cease-fire collapsed earlier this week, and fighting has persisted since then.
More than 2,100 Palestinians, including close to 500 children, have been killed since the Gaza war began on July 8, according to Palestinian officials and U.N. figures. Israel lost 64 soldiers and four civilians. The U.N. says three-fourths of those killed in Gaza have been civilians.
Israeli Prime Minister Benjamin Netanyahu blamed Hamas for the collapse of the most recent cease-fire. In a phone conversation with U.N. Secretary General Ban Ki Moon, Netanyahu alleged that Hamas has violated 11 cease-fires since the war started, Netanyahu's office said.