British Transport Police (BTP) are searching for a man after an Underground worker was racially abused when she asked a customer to put a mask on.
CCTV footage taken just before 6pm on 13 October at Morden Underground station, south London, shows a man approach a female staff member to ask for help with his Oyster card.
The worker noticed the customer was not wearing a face mask and asked him to put one on before she assisted him.
However, BTP say the man refused to put on a face covering and began shouting at the staff member before entering a shop at the station.
After emerging from the shop, the man approached the worker again and racially abused her, BTP said.
He left the station following the incident but reportedly returned the next day to take a photo of the member of staff before exiting.
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Officers have released a CCTV image of a man who may have information which could assist their investigation.
It is mandatory for customers on public transport to wear face masks under current coronavirus regulations. First-time offenders face a fine of up to £200 but fines are doubled at each offence up to a maximum of £6,400.
Exemptions to the rule is made for people with valid medical reasons.
BTP have urged anyone who recognises the man in the photo to text 61016 or call 0800 40 50 40 quoting reference 369 of 13/10/20.
Alternatively, you can call Crimestoppers anonymously on 0800 555 111.
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