Israel's defence minister says "Gaza is burning" after heavy strikes overnight targeted Gaza City, with news sites reporting the military launched a ground offensive to seize the enclave's largest urban centre.

The US news site Axios cited Israeli officials as saying the operation marked the start of a ground offensive in the Gaza Strip's largest city.

Palestinian media said tanks later entered the city, where hundreds of thousands of people are believed to remain.

The Israeli military did not immediately respond to request for comment on the reported move, which comes after weeks of intensive Israeli strikes on the city.

The military has laid siege to the Gaza Strip, creating a humanitarian catastrophe with widespread destruction, mass displacement and severe shortages of food and wat

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