Israel has confirmed it caused an explosion at a refugee camp in the northern Gaza Strip, saying it targeted a Hamas leader.
Reuters reports Palestinian medics say at least 50 are dead.
CNN reports the Israel Defence Force says it was targeting a very senior Hamas commander in the area around the camp.
US Correspondent Richard Arnold told Mike Hosking that the director of a hospital nearby said that hundreds of dead and injured have arrived at the hospital, and many are still under the rubble.
This figure is still unconfirmed.
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