Michael Conlan, Ireland's Olympic bronze medallist in boxing, has lost his mobile phone complete with all the photos he took during the Games in London.
The 20-year-old was clubbing with fellow team mates in Dublin after a reception for Team Ireland had been held earlier in the day in the city centre.
"He realised pretty quickly that he'd either dropped his phone or he was pickpocketed - he can't say for sure and doesn't know exactly when it went missing.
"Nobody has handed it in yet, and we'd appeal for anybody who picks it up to hand it in to the police," his father John told the press.
His photos featured athletes like Usain Bolt and Serena Williams, as well as Michael's team mates enjoying their medal-winning moments.
The night out at Copper Face Jacks nightclub on Wednesday was the first chance for the athletes to get together and unwind since their return from London on Tuesday.