British Transport Police are investigating an outraging public decency incident at Paisley Gilmour Street station.
At 4pm on Friday, June 25 it was reported a man and woman engaged in an indecent sexual act in front of a member of public on platform 4 at the station.
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The man is described as being of slim build, with blue eyes and star tattoos on his neck. He was wearing a black Under Armour cap, with a black hoodie, trousers and trainers.
The woman is described as being of slim build, wearing a black cap with a pink jacket, black leggings and white trainers.
A BTP spokesman said: "Officers are keen to speak to anyone who may have witnessed the incident to help with their investigation."
Witnesses, or anyone with information, can contact BTP by texting 61016 or calling 0800 40 50 40 quoting reference 395 of 25/06/21.
Alternatively, you can phone Crimestoppers anonymously on 0800 555 111.