Lee McLaughlin from Gleneely in Inishowen is missing in Paris.
The 19-year-old was in the city along with his father and nephew for Ireland's game against Sweden on Monday evening.
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Lee was last seen leaving the Ibis Paris Montmartre hotel at 12pm on Tuesday afternoon.
Attempts to contact him by phone failed. He did not board his flight home or turn up at the airport.
Lee's family have issued the following appeal:
