Israeli artillery were fired on Gaza Monday morning, as hostilities entered a second week.
Overnight Israel launched dozens of air strikes on Gaza and the Hamas Isamists who rule the strip where 2 million Palestinians live.
The sound of explosions roared, as dozens of fighter jets bombed what Israel said were underground tunnels used by Hamas.
Meanwhile, militants in the Palestinian enclave fired rockets at the southern Israeli cities of Beersheba and Ashkelon.
Israeli aircraft struck nine residences belonging to high-ranking Hamas commanders, the military said.
Prime Minister Benjamin Netanyahu said Israel's campaign in Gaza was continuing at "full force," and that deterrence had to be achieved to prevent future conflict with Hamas.
U.S President Joe Biden said his administration was working with all parties to achieve sustained calm.
"We also believe Palestinians and Israelis equally deserve to live in safety and security and enjoy equal measure of freedom, prosperity and democracy."
Yet there's no sign of an end to hostilities, despite international calls for a ceasefire.
It follows a crescendo of global concern over the weekend, after an Israeli air strike in Gaza destroyed several homes, killing 42 people, including 10 children.