Police are still searching for bronze medals allegedly stolen from two of Britain's Olympic heroes.
The medals were taken from rower Alex Partridge and hockey star Hannah Macleod as they partied at a nightclub in London's Mayfair in the early hours of Wednesday morning.
The pair began their night out at a Buckingham Palace reception hosted by the Queen to celebrate London 2012 athletes.
A 31-year-old man has been arrested in connection with the inquiry and is being questioned at a west London police station, a Scotland Yard spokesman said.
Macleod said in a message on Twitter that she was "totally devastated". She added: "I'm not after punishment. If you picked up a Bronze Olympic medal that isn't yours pls just send anonymously back to GB hockey-Bisham Abbey."
A Metropolitan Police spokesman said the Olympians were at the Mahiki nightclub when they left their jackets unattended with the medals inside.
"Some time later both parties realised their jackets, and the medals inside them, were gone," the spokesman said. "At approximately 11.30am today the jacket belonging to the man, but not containing the medal, was handed in to a north-west London police station. Inquiries continue to try and trace both medals and the jacket."
The athletes published a photo of a man captured on CCTV who they wished to talk to about the alleged thefts.
Partridge wrote: "The London Met are doing a great job and following up on all our leads, but massive thank you to everyone else for spreading the word."
Detective Chief Inspector James Harman said: "I would appeal to anyone who was in the venue in the early hours of Wednesday and saw anything suspicious to contact us - any information, no matter how insignificant it may seem, could prove vital to this investigation. My team have spoken to both Olympians who are understandably desperate to be reunited with the medals they have dedicated their careers to win. If you know who is responsible or where the medals are, please call us."