Prosecutors announced the results of the probe into the death of Mawda Shawri, after officials said on Friday that she had died from a bullet wound in the incident on May 17 but did not say who had fired it.
The prosecutor's office in the southern town of Mons said the investigation showed only one bullet had been fired "during a dangerous high-speed chase over 60 kilometres (36 miles)" and traced it to a police officer.
"The officer who opened fire is overcome and disconsolate. He neither wanted nor could have imagined this," prosecutor general Ignacio De la Serna told reporters, according to the Belga news agency.
"It's a tragic event that everyone regrets, including the police officers," he added.
The police officer who fired the shot had appeared before a judge, who is reviewing all the evidence before deciding whether to press any charges, the prosecutor said.
The lawyer for the girl's family, Olivier Stein, told AFP that the prosecutors could have avoided confusion over how the girl died if they had questioned his clients directly.
But instead, he said, they had "treated them more like offenders than victims."
Stein said judicial authorities had told him the bullet was fired "at a moment when the van was travelling at 90 kilometres per hour" as police squad cars moved beside it.
(Except for the headline, this story has not been edited by NDTV staff and is published from a syndicated feed.)
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