A 12-storey apartment block in Gaza City has collapsed after being struck by an Israeli missile.

According to eyewitness reports, Israeli aircraft fired an early warning, non-explosive rocket at the roof of the building, which was followed by two missiles, sending a fireball into the sky and causing nearby buildings to shake.

Ayman Sahabani, the head of the emergency room at Gaza City's Shifa Hospital confirmed that 22 people, including 11 children, were wounded in the airstrike.

Israel justified the attack, claiming Hamas militants were using the building as a command centre.

The bombardment came hours after an attack on the southern Israeli village of Sdot Negev, in which a four-year-old died.

The boy is the fourth civilian in Israel to be killed in an attack since the outbreak of conflict on July 8.

Israel warned of reprisals vowing that "Hamas will pay a heavy price" for the death of the Israeli child.

The latest round of airstrikes marks an escalation in military action following a breakdown of Egyptian-brokered cease-fire talks and the collapse of a temporary truce earlier this week.

The Egyptian Foreign Ministry has now urged Israel and Hamas to resume indirect talks and agree to an open-ended cease-fire.

Israeli government spokesman Mark Regev had no immediate comment regarding the renewed call for a cease-fire.

Sami Abu Zuhri, a spokesman for Gaza's ruling Hamas, said the group would consider the Egyptian appeal, but there was no sign it would budge from longstanding demands.

So far more than 2,000 Palestinians have been killed in the conflict, many of them children.

64 Israeli soldiers have also been killed in the conflict.