The police need a witness to make a positive ID.

警方需要有目击者加以确认。

《牛津词典》

Police are trying to find a vital witness who may have seen what happened.

警察正努力寻找一名可能看到事情的经过的重要目击者。

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Another witness who gave his first name as Fabio said he tried to warn police before the stampede occurred that a catastrophe was building.

另一位自称叫法比奥的目击者表示，在人群蜂拥而至之前，他曾警告过警察说再这样下去会有灾难发生的。

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The police witness said the accused had also told a potential witness in the case that she would break her legs and kill her.

BBC: Ballymurphy area of west Belfast

Police witness, Pc David Moran said Rooney confessed to murdering someone after they detained him for an unrelated matter a few hours after the attack.

BBC: Longstone Park Pic: Lisa Summers

On his third attempt, the case was sent to the Court of Appeal after new information came to light regarding the credibility of the main police witness, the Criminal Cases Review Commission (CCRC) said.

BBC: Martin Foran 1985 robbery conviction quashed