Israeli Air Force jets bombed several Hamas targets after the group fired thousands of rockets at Israel this morning.
The Israel Defence Forces (IDF) posted a video on X showing Hamas targets being struck by missiles and smart bombs.
"Dozens of air force fighter jets attacked targets of the Hamas terrorist organisation in the Gaza Strip a short time ago. The IDF appeals to the public to obey the instructions of the Home Front Command, which save lives," the IDF said in the post on X.
Israeli Prime Minister Benjamin Netanyahu said Israel was at "war" with Hamas. "We are at war, not in an operation or in rounds, but at war," the Israeli leader said in a statement, adding Hamas had launched a "murderous surprise attack" on Israel and its people.
"I have ordered an extensive mobilisation of reserves and that we return fire of a magnitude that the enemy has not known. The enemy will pay an unprecedented price," he said.
Israel's army said it was fighting Gaza terrorists who entered Israel by land, sea and air using paragliders.
It was a combined ground raid which happened through paragliders, through the sea and through the ground, Israel army spokesman Richard Hecht told reporters. "Right now we're fighting. We're fighting in certain locations around the Gaza Strip... our forces are now fighting on the ground" in Israel, he added.
Mr Hecht confirmed there are casualties but would not be drawn on details, nor discuss reports that multiple Israelis had been captured by Palestinian terrorists.
Thousands of military reservists are set to be drawn up for Gaza, as well as northern Israel, near foes Lebanon and Syria, and the occupied West Bank.
With inputs from AFP
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