Israel using small drones to visually inspect sites before troops go in

 Wall Street Journal:

The Israeli military has tried a variety of methods to explore Hamas’s tunnels in Gaza: robots, robot dogs and real dogs. In the dense urban battlefield of Gaza, the Israeli military has been flying these quadcopters—essentially small helicopters with four rotors—into buildings before sending in soldiers. 

The small drones are just one new piece of Israel’s unmanned aerial arsenal, which military officials say has played an essential role in minimizing their casualties as they rapidly advance through a densely populated, well-fortified and extensively booby-trapped battlefield.
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Hamas is not a traditional enemy that adheres to the rules of warfare such as they are.  They hide in tunnels and other areas rather than engage in traditional offensive and defensive positions. 

See also:

Israeli raids in West Bank target Hamas funding

Israeli forces raided foreign exchange and money transfer agencies in Ramallah and other cities in the occupied West Bank on Thursday, seizing millions of dollars suspected of being intended to fund the Islamist group Hamas, the military said.
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