Israeli strike kills at least 19 in a Gaza tent camp as Blinken slams Israel after IDF says its forces likely shot slain American activist

US Secretary of State Anthony Blinken has called for "fundamental changes" to the way Israeli forces operate in the occupied West Bank after the killing of American activist Aysenur Ezgi Eygi at a protest last week.

It comes as an Israeli strike hit a crowded Palestinian tent camp early on Tuesday in Gaza, killing at least 19 people and wounding 60, Palestinian officials said.

Israel said it targeted senior Hamas militants with precise munitions.

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The overnight strike occurred in Muwasi, a sprawl of crowded tent camps along the Gaza coast that Israel designated as a humanitarian zone for hundreds of thousands of displaced civilians to seek shelter from the nearly year-old Israel-Hamas war.

Associated Press video showed three large craters at the scene. First responders dug through the sand and rubble with garden tools and their bare hands, using mobile phone flashlights until the sun came up.

They pulled body parts from the sand, including what appeared to be a human leg.

"We were told to go to Muwasi, to the safe area ... Look around you and see this safe place," said Iyad Hamed Madi, who had been sheltering there.

"This is for my son," he said, holding up a bag of diapers. "He's four months old. Is he a fighter? There's no humanity."

Gaza's Health Ministry said the death toll may rise as more bodies are recovered. The Civil Defence, first responders who operate under the Hamas-run government, had earlier said 40 people were killed. The Israeli military disputed that toll.

The ministry is also part of the Hamas-run government. Its figures are widely seen as reliable.

The Hamas government's media office issued a statement explaining that the death toll discrepancies arose from different methods of counting the dead, saying the Health Ministry counts only bodies taken to hospitals while the Civil Defence also counts bodies that have not yet been retrieved.

An Associated Press cameraman at Nasser Hospital in Khan Younis saw 10 bodies in the morgue, including two children and three women. It was one of three medical centres that received casualties, according to the Civil Defence.

"We were sleeping, and suddenly it was like a tornado," Samar Moamer told the AP at Nasser Hospital in Khan Younis, where she was being treated for wounds from the strike. She said one of her daughters was killed and the other was pulled alive from the rubble.

The Israeli military said it struck Hamas militants in a command-and-control centre embedded in the area. It identified three of the militants, saying they were senior operatives who were directly involved in the October 7 attack by Hamas that triggered the war and other recent attacks.

Rear Adm. Daniel Hagari, an Israeli military spokesperson, disputed the initial casualty reports in a post on the social media platform X, saying they "do not line up with the information available to the (Israeli army), the precise weapons used and the accuracy of the strike."

Hamas released a statement denying that any militants were in the area and calling the Israeli allegations a "blatant lie." Neither Israel nor Hamas provided evidence to substantiate their claims.

Israel says it tries to avoid harming civilians and blames Hamas for their deaths because the militants often operate in residential areas and are known to position tunnels, rocket launchers and other infrastructure near homes, schools and mosques.

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'Unprovoked and unjustified'

Blinken's sharply worded rebuke came after the Israel Defence Forces (IDF) said on Tuesday that it was "highly likely" that Eygi was "hit indirectly and unintentionally by IDF fire".

In its initial inquiry into the incident, the IDF said that the shot was not aimed at the activist, but at "the key instigator" of a "violent riot" at the Beita Junction where it said Palestinians burned tires and hurled rocks at Israeli security forces. It didn't name the alleged instigator.

The International Solidarity Movement (ISM), with whom Eygi had been volunteering, said that its protest on September 6 was peaceful.

At a news conference in London on Tuesday, Blinken said Eygi's killing was "unprovoked and unjustified" and demanded changes to the rules of engagement of Israel forces operating in the West Bank.

"No one, no one should be shot and killed for attending a protest. No one should have to put their life at risk just for expressing their views," he said.

"Now we have the second American citizen killed at the hands of Israeli security forces. It's not acceptable. It has to change. And we'll be making that clear to the senior-most members of the Israeli government."

Family says Israel's inquiry is 'wholly inadequate'

The family of the 26-year-old activist said they were "deeply offended by the suggestion that her killing by a trained sniper was in any way unintentional," reiterating calls to US leaders for an independent investigation into her death.

Eygi, who was born in Turkey, was shot while taking part in a weekly protest against an Israeli settlement near the Palestinian village of Beita. All Israeli settlements are considered illegal under international law.

She was a recent graduate of the University of Washington, and had been volunteering with the same pro-Palestinian activist group as Rachel Corrie, a US citizen killed in 2003 while attempting to stop an Israeli bulldozer from demolishing Palestinian homes in Gaza.

Eygi's family, who have previously blamed Israel for her killing, said the findings of the Israeli inquiry were "wholly inadequate".

"This cannot be misconstrued as anything except a deliberate, targeted and precise attack by the military against an unarmed civilian," the family said.

The ISM also dismissed Israel's "specious claim" that Eygi was unintentionally hit by IDF fire, describing the slain activist as "one of the hundreds of thousands of martyrs Israel has killed over decades of ethnic cleansing, displacement, and genocide."

"The military's account of the events is blindly based on the accomplices' version, which completely contradicts the testimonies of multiple eye witnesses, who the military did not even contact," the group said in a statement on Tuesday.

"All eyewitnesses said immediately following the killing that the scene where Aysenur was killed was completely quiet, and that there could have been no excuse to open fire, let alone directly hitting a woman peacefully standing in an olive grove."