British Transport Police said the man was attacked at about 11.30am on Saturday following an altercation at East Croydon station.
The force said he was attacked “with what is believed to be broken glass”.
London Ambulance Service took the victim to hospital, where he is being treated for his injuries.
They are believed to be non-life threatening.
Officers are asking anyone who was in or around East Croydon station, and saw anything suspicious, to get in touch. Call 0800 40 50 40, quoting reference 194 of August 24, 2019.
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