At least 27 Palestinians have been killed in what is being called Israel's largest offensive in the Gaza Strip in nearly two years.
The Isrealis say they are responding to rocket attacks from Hamas militants based in Gaza.
Some of those rockets have reached as far as Tel Aviv, the capital.
The Israeli military says its warplanes attacked over 130 sites, including Hamas command centers, earlier today.
It has also mobilized forces along the border for a possible ground invasion.
The health ministry in Gaza says four women and three children are among those killed in the air strikes.
Meanwhile, Palestinian President Mahmoud Abbas has appealed for international help as the conflict between Israel and Hamas continues to escalate.
"What's happening in the Gaza Strip, the West Bank and East Jerusalem is not a war between two armies. The Palestinian people are an unarmed people, people who live under occupation. It's time now for the international community, and especially the Quartet and the Security Council, to take their responsibility to guarantee the international protection of our people."
The surge in violence along the Gaza border follows a chain of events that started with the abduction of three Jewish students in the occupied West Bank last month.
Blaming Hamas, the Israelis arrested hundreds of its activists in their search for the teenagers who were eventually found dead.
