GAZA CITY, Gaza Strip (AP) - The heaviest fighting in four years between Israel and militants in the Gaza Strip has brought life to a standstill on both sides of the border.

Gaza's streets are mostly empty today as the Israeli air force continues to strike targets. Across southern Israel, residents remain huddled in doors or close to home.

Militants in Gaza have been pounding southern Israel with rocket fire today, killing three people.

It's the second day of intense Israeli air raids and naval attacks on militant targets. And Israel is threatening to invade the Palestinian territory.

After yesterday's assassination of Hamas mastermind Ahmed Jabari, Israeli tanks, gunboats and aircraft struck dozens of sites across Gaza. According to Palestinian medical officials, a total of 15 Palestinians, including seven civilians, have been killed, and more than 100 others wounded.

Israel says yesterday's assassination was the start of a broader offensive that was launched after days of rocket fire from Gaza into southern Israel.

In recent years, Hamas has beefed up its arsenal with more powerful and far-reaching missiles. Israel, meanwhile, has deployed a system that shoots down incoming rockets.

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