Israeli airstrikes on Gaza City flattened three buildings and killed at least 26 people on Sunday.
The strike makes it the deadliest single attack since heavy fighting broke out between Israel and Hamas nearly a week ago.
The Gaza Health Ministry said 10 women and eight children were among those killed, with another 50 people wounded in the attack.
In a televised speech Israeli Prime Minister Benjamin Netanyahu said Israel will continue to strike Gaza “as long as necessary”.