Ibrahim Mahmoud picked up the phone in his appliance shop in the Bureij refugee camp in central Gaza. On the other end was a woman speaking Hebrew-accented Arabic, warning him to get his family out of his house before it is bombed.

It's a new Israeli tactic in a monthlong offensive against Hamas and other terrorists in Gaza, hitting houses of suspected terrorists but warning them to get their families out first. The Israeli military usually describes the structures as weapons storage facilities.

The military says the aim is to reduce civilian casualties. Another tactic is leaflets dropped from aircraft, warning people to stay away from militants. Also, the Israeli military broadcasts over radio frequencies used by Hamas, warning residents to distance themselves from the militants.

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The offensive began after Hamas-linked terrorists tunneled under the Gaza-Israel border on June 25 and attacked an Israeli army post, killing two soldiers and capturing a third. More than 120 Palestinians, including many civilians, have been killed in ground assaults, artillery barrages and airstrikes.

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Israel has said repeatedly it is trying to reduce civilian casualties, blaming terrorists from operating in crowded areas.

This week in the southern city of Khan Younis, about 1,000 residents answered their phones and heard a recorded Israeli army warning to them not to harbor militants or hide weapons. The Palestinian phone company said the numbers were apparently picked at random.

Government officials said hospitals and government buildings received phone warnings, officials said.

Palestinian officials don't accept the Israeli tactic as an effort to spare lives. They see sinister motives.

Government spokesman Ghazi Hamad said the Israeli calls are a "criminal act" that targets civilians and government buildings. The campaign aims to drive people out of their homes, paralyze the government, and "demoralize" the population, he said.

The army spokesman said the calls are to specific homes or areas. He refused to say how they got the numbers.

Mahmoud said the woman who called his shop accused him of working with Hamas and selling weapons. He denied that, and later the same person called back and said his house was not a target after all. "She ended the call with 'be safe'," he said. But by then he had moved 20 family members out of his four-story house.

"They terrorized the whole family," Mahmoud said.

Many others are exasperated by the warnings.

Othman Shbeir, a Palestinian security officer from Khan Younis whose militant brother was killed in an airstrike recently, said he got the evacuation order in the middle of the night,

He and dismissed as a joke, until neighbors warned him that a nearby house of an Islamic Jihad activist was bombed the same night.

Two days later, his three-story house was still standing empty.

"It is better if they just bring the house down," he said. "We are living in terror and no one can come near the house."

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