Police investigate off-duty cop who restrained 13-year-old girl on Perth train

WA Police are investigating an incident on a Perth train during which an off-duty officer restrained a 13-year-old girl.

CCTV from the train is being reviewed, which WA Police says is part of a standard process.

The Public Transport Authority's CCTV is being kept under wraps for now, however, there is vision circulating on social media that was recorded by the girl's friend.

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The phone footage shows the off-duty officer restraining the 13-year-old on the ground, before pushing her onto a seat on Sunday about 4pm on the Yanchep Line.

In the footage the girl's friends can be heard screaming "her head, her head" after the officer appears to pin the girl down at one point.

Police today said the 13-year-old had allegedly assaulted the officer by punching him in the face after he intervened in a verbal altercation between two groups.

While no formal complaint has been made by those involved, police are investigating the officer's conduct.

However, he is still on operational duties during the investigation.

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