A US senator has dismissed an Israeli army report that claims a soldier accidentally killed the Palestinian American journalist Shireen Abu Aqleh in the midst of a gun battle, saying it is unsupported by the evidence.

Chris Van Hollen, a Democratic senator for Maryland, repeated his call for an independent US investigation into Abu Aqleh’s killing in the West Bank in May, saying that the United Nations and reconstructions by major news outlets found that the Al Jazeera television journalist was not in the immediate vicinity of fighting with Palestinian militants and could not have been caught in the crossfire.

“The crux of the ‘defense’ in this IDF [Israel Defence Forces] report is that a soldier was ‘returning fire’ from militants” when Abu Aqleh was struck, Van Hollen tweeted. “But investigations … found no such firing at the time. This underscores need for independent US inquiry into this American journalist’s death.”

On Monday, more than four months after her killing, Israel finally admitted that it was “highly probable” that an Israeli soldier shot Abu Aqleh while she was reporting on a military raid on the occupied West Bank city of Jenin.

The report said Abu Aqleh was probably shot by an Israeli soldier who was under fire from a group of Palestinian gunmen. It claimed the soldier was using a telescopic sight and misidentified her as one from his armed opponents. The army said no crime was committed so no one will be prosecuted.

However, eyewitness accounts and videos of Abu Aqleh and the area around her at the time of her killing do not show a gun battle. She was also wearing body armour and a helmet clearly labelled as “press”.

A United Nations investigation said that Israeli soldiers fired “several single, seemingly well-aimed bullets” at Abu Aqleh and other journalists.

Investigations by the New York Times, CNN, the Washington Post and other media questioned the official Israeli version of events. The New York Times said there were “no armed Palestinians near her when she was shot” and that its investigation “contradicted Israeli claims that, if a soldier had mistakenly killed her, it was because he had been shooting at a Palestinian gunman”.

The Committee to Protect Journalists called the Israeli report “late and incomplete”.

“They provided no name for Shireen Abu [Aqleh’s] killer and no other information than his or her own testimony that the killing was a mistake,” it said.

The White House pressured Israel to reveal its findings amid demands for an independent US investigation from some members of Congress and Abu Aqleh’s family which accused Joe Biden’s administration of covering for Israel. Critics noted that the report was released on the Labor Day public holiday in the US when it was likely to receive less attention.

The journalist’s niece, Lina Abu Aqleh, said the family had no confidence in the Israeli report.

“We could never expect any type of accountability or legitimate investigation from the very entity responsible for gunning down an unarmed and clearly identifiable journalist,” she said.

The family said an independent American investigation was “the bare minimum the US government should do for one of their own citizens”. But it also called for an international criminal court investigation, calling Abu Aqleh’s killing a “war crime”.

Critics say the Israeli military has a long history of dissembling and making false claims over the killings of civilians while waiting for attention to move elsewhere. But the Abu Aqleh family was able to maintain interest in the case, and pressure on the Biden White House, because she was a US citizen.

Israel’s account shifted several times over the four months since the journalist was shot.

Immediately after the killing, the Israeli prime minister at the time, Naftali Bennett, said it “appears likely that armed Palestinians, who were firing indiscriminately at the time, were responsible”.

The Israeli embassy in Washington posted a tweet purportedly showing the Palestinian gunmen who killed Abu Aqleh and then deleted it. The Israeli government released footage that created the impression the journalist was in the midst of a major battle. The Israeli human rights group, B’Tselem, released its own video showing that the government’s footage was filmed several blocks from where Abu Aqleh was shot.

As criticism grew, Bennett’s office condemned “hasty accusations against Israel”, and pro-Israel pressure groups attacked media investigations of the killing which challenged the official version.

During the following weeks, the Israeli army admitted that one of its soldiers may have been responsible but claimed it was not able to carry out a proper investigation because the Palestinian Authority would not cooperate and hand over the bullet that killed the journalist.

The US state department said it welcomed the “review of this tragic incident”. But it faced criticism for sidestepping demands that the soldier or soldiers responsible be held to account and for instead calling for “policies and procedures to prevent similar incidents from occurring in the future”.