Israel said on Tuesday it had reclaimed control of the Gaza border, pounding the enclave with the fiercest air strikes in the 75-year history of its conflict with the Palestinians despite a Hamas threat to execute a captive for each home hit, writes Reuters.

Israel has vowed to take its “mighty revenge” since gunmen rampaged through its towns, leaving streets strewn with bodies in by far the deadliest attack in its history. It has called up hundreds of thousands of reservists and placed the Gaza Strip, crowded home to 2.3 million people, under a total siege.

Israeli media said the death toll from the Hamas attacks had climbed to 900 people, mostly civilians gunned down in their homes, on the streets or at a dance party, dwarfing the scale of any past attack by Islamists apart from 9/11. Scores of Israelis were taken to Gaza as hostages, with some paraded through the streets.

Nearly 700 Gazans have since been killed in Israeli strikes, according to Gaza officials, while whole districts in Gaza have been flattened.