Israeli military strikes across the Gaza Strip have killed at least 21 Palestinians, local health authorities say, as Israeli forces operated in Rafah near the border with Egypt, escalating a new week-long aerial and ground offensive.

According to Reuters, health officials said Israel has killed nearly 700 Palestinians since it resumed attacks on Gaza last Tuesday, ending weeks of relative calm after a ceasefire in January.

They said the deaths included at least 400 women and children.

Hamas said several of its senior political and security officials had also been killed.