GAZA CITY, Gaza Strip (CBS News) -- The cross-border war between Israel and the Palestinians in Gaza escalated dramatically Thursday. President Barack Obama called Israeli Prime Minister Benjamin Netanyahu and offered U.S. help to arrange a cease-fire.
Israel's military says the Palestinians fired well over 100 rockets in residential areas of Israel. Many of them were intercepted by the country's missile defense system.
The Israelis say their aerial assault on Gaza hit about 500 targets.
So far this week at least 80 Palestinians, most of them civilians, have been killed.
All this was sparked by the kidnapping and murder of three Jewish students in the West Bank last month and the revenge killing of a Palestinian teenager.
In broad daylight on a busy street in Gaza Thursday, a car was incinerated by an airstrike.
Islamic Jihad, a Palestinian militant group, told CBS News two of the three men who were killed were its members.
Israel also targets what it calls command centers - though, in reality, they're often the homes of militants.
To give their families a chance to evacuate, the Israeli military sometimes telephones in advance - or fires a small missile without an explosive as a warning. And the strikes are pin-point accurate. The front gate is all that's left of a house, barely 10 feet wide, was hit Thursday afternoon - leaving the rest of the street unscathed.
The residents were warned via telephone and all of them survived.
But the system doesn't always work - and a rising civilian death toll is stoking Palestinian anger.
On Thursday they buried more of their dead in Gaza - some of them children.
A family of eight was killed in one home on Tuesday.
The Israeli military said they were given a warning and made it out in time, but they returned too soon - just as the strike hit.
The family's neighbor Reda Kaware gave us a different version of events.
"The family cannot be able to leave because is not give a lot of time to leave their home," she said.
Israel claims the militants in Gaza are using civilians as human shields -- for instance, by launching rockets from residential areas.
The Israeli military said Thursday nearly 150 missiles were fired at Israel. They caused some damage to buildings but so far no Israelis have been killed, thanks in part to Israel's Iron Dome missile defense system, which shoots down many of the rockets.
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