British Transport Police are appealing for witnesses after a member of rail staff was head-butted at Thornton Heath station.

Officers have released CCTV images of a man they want to speak to in connection with the violent attack, which happened at about 9.20am at the entrance to the station on Thursday June 21.

A member of staff at the ticket barriers advised a man trying to get into the station, that he was not permitted to use his Freedom Pass until after 9.30am.

The man became argumentative and aggressive and after following advice to go and buy a ticket, he returned to the barrier where he pushed the member of staff in the chest and head-butted him before leaving the station.

Enquiries into the incident are ongoing. Officers have made return visits to the station and have spoken to witnesses to try and identify the man.

Detective Sergeant Robert Stokoe from Croydon BTP station said: "The member of staff was attacked for simply doing his job and pointing out, quite rightly, the man couldn't use his Freedom Pass before 9.30am.

"Fortunately the victim was unhurt but we are keen to find this man and question him about this violent and unprovoked attack."

It is believed the man was travelling to Selhurst or Croydon.

A spokesman for Southern said: "This attack was entirely unprovoked and is another example of brutish and violent behaviour which is totally unacceptable.

"We urge anyone who recognises this man to come forward and identify him to BTP."

If you have any information please call British Transport Police on 0800 40 50 40 or Crimestoppers, anonymously, on 0800 555 111. In all calls please quote background log B6/LSA of 29/06/2012.