Gaza’s fragile ceasefire was shattered early Tuesday as Israel carried out deadly strikes across the enclave and Israeli Prime Minister Benjamin Netanyahu vowed to use “increasing military strength” against Hamas.

The death toll rose to more than 400, Gazan authorities said, marking one of the deadliest days since the war began. The attacks came after a breakdown in talks to release hostages.

DEIR AL-BALAH, Gaza Strip (AP) — Israel launched airstrikes across the Gaza Strip early Tuesday, killing more than 400 Palestinians, local health officials said, and shattering a ceasefire in place since January with its deadliest bombardment in a 17-month war with Hamas.