By Emily Rose

JERUSALEM (Reuters) - The Israeli military drastically underestimated the capabilities of Hamas before its attacks on Israel on October 7, 2023, and "failed in its mission to protect Israeli civilians", a summary of an Israeli military investigation published on Thursday said.

The perception that Hamas was not interested in a full-scale conflict and that Israel would have ample warning if that changed went unchallenged for years, the summary said, resulting in a lack of preparedness and ability to respond to an attack.

"The belief was that Hamas could be influenced through pressures that would reduce its motivation for war, primarily by improving living conditions in the Gaza Strip," the report said.

The investigation looked at Israeli military strategy, battle behaviour and intelligence before, during and after October 7, 2023, when Hamas fighters stormed southern Israel, killing 1,200 people and taking more than 250 hostages, according to Israeli tallies.

More than 48,000 people have been killed in Israel's assault on Gaza since then, according to Palestinian health officials. Much of the enclave has been laid waste and most of the territory's 2.3 million prewar population have been displaced multiple times, humanitarian agencies say. Around 400 Israeli soldiers have also been killed.

The military investigation was conducted as calls grow from within the Israeli opposition and civil society for a national inquiry into the government's failures on the deadliest single day in modern Israeli history.

Israeli Prime Minister Benjamin Netanyahu has said a national inquiry would only be appropriate after the conclusion of the war.

The first phase of a ceasefire that began on January 19 is due to expire in two days time.

The military investigation found Israel had focused its intelligence and military efforts on other fronts, such as Hezbollah in Lebanon, and relied too heavily "on intelligence, barriers, and defensive measures alone", and was thus caught by surprise.

Military commanders did not perceive an urgent threat leading up to October 7 attacks and did not reinforce the troops defending the border.

A statement from the Israeli Prime Minister's Office on Thursday said that the military had not given the prime minister the findings of its investigations into the war.

(Reporting by Emily Rose; Editing by Alex Richardson)