Israel's top military prosecutor described as "very grave" on Monday an air strike on Rafah which according to Gaza health authorities killed dozens of Palestinian civilians, and said an after-action investigation by the armed forces continued.

"The details of the incident are still under an investigation, which we are committed to conducting to the fullest extent," Major-General Yifat Tomer Yerushalmi told a conference hosted by the Israel Bar Association.

"The IDF (Israel Defence Forces) regrets any harm to non-combatants during the war."