The Israeli bombardments this Friday in the Gaza Strip left at least 15 dead, the Israeli army said, specifying that the operation is directed against the Islamic Jihad organization and that "it is not over yet".
It is "a preventive attack" in which "we estimate that about 15 people were killed," army spokesman Richard Hecht told reporters. The operation "is not over yet," he added.
Islamic Jihad said on Friday that a top commander in the group had been killed in Israeli strikes.
Local officials reported casualties and television footage showed smoke billowing from a building.
A spokesman for the Gaza Health Ministry said there were several casualties and a state of emergency was declared. Television images showed black smoke billowing from the roof of a building in the densely populated strip.
The attacks came after Israel arrested Bassam al-Saadi, a senior leader of the Palestinian Islamic Jihad group, during a raid in the occupied West Bank city of Jenin earlier this week.
Israel subsequently closed all Gaza crossings and some nearby roads for fear of retaliatory attacks by the group, which has a stronghold in Gaza.
"The enemy has started a war against our people and against us and we will defend ourselves and our people," Islamic Jihad said in a statement.
With information from AFP and Reuters