Announcing the findings, the Palestinian attorney general said “the only shooting was by the occupation forces, with the aim of killing”.
The Israeli defence minister rejected the report, calling it “a blatant lie”.
Israel’s army is carrying out its own investigation, and has said Palestinian militants might have shot Abu Aqla.
There was widespread outrage when the 51-year-old Palestinian-American journalist was shot dead while reporting on an Israeli military operation in Jenin, in the occupied West Bank, on 11 May.
Eyewitnesses say the fatal shot was fired by Israeli forces, though Israel disputes this. It says it has not yet been possible to establish the source of the gunfire because the Palestinians rejected its request to examine the bullet that killed Abu Aqla or to hold a joint investigation.
Israel says it has identified a soldier’s weapon which might have fired the shot, but that it cannot be certain without analysing the bullet.
At a news conference in the West Bank city of Ramallah, Palestinian Attorney General Akram al-Khatib said the bullet that killed Abu Aqla was a 5.56mm (0.219 inch) round with a steel component used by Nato forces.
He said Palestinian authorities would not hand over the bullet to the Israelis, and that no photograph of it would be published either. Palestinian officials have previously said they do not trust Israeli investigators.
Abu Aqla, who was wearing a protective vest with the word “Press” on it as well as a helmet, was shot in a road near where a gun-battle had taken place between Israeli forces and Palestinian militants. Her producer, Ali Samoudi, was shot in the back but survived.