Israel has warned Palestinians in northern Gaza to leave the area before it starts firing at Hamas targets.
The country's air force has been dropping leaflets in the area - saying "those who fail to comply with the instructions will endanger their lives and the lives of their families".
Israel says it intends to attack what it calls "terrorists and terror infrastructures" in response to rocket fire coming from the Gaza strip.
Israel briefly deployed ground troops inside Gaza overnight - the first time it's done so during this conflict.
At least 159 Palestinians have died in the air strikes.
The UN Security Council yesterday called for a ceasefire and peace talks.
