French Police have confirmed the death of a Darren Rodgers, a 24 year old Northern Ireland.
It is believed the late Rodgers was on his own and fell about eight metres from a promenade onto a rocky beach.
Supt Nigel Goddard, who is leading the PSNI team in France, said he was told it was an accident and not in any way disorder related.
Northern Ireland played Poland in the city on Sunday night in their first match of Euro 2016 and the accident happened in the early hours of Monday.
Mr Rodgers was from the Meadowvale area of the County Antrim town and was a former pupil of Cambridge House Grammar School.
In a statement, his family thanked the local community for their support.
Northern Ireland’s first and deputy first ministers, Arlene Foster and Martin McGuinness, issued a joint statement.
“It was with great shock and sadness we learned this morning of the death of Darren Rodgers in Nice last night as the result of a tragic accident,” they said.
“The loss of a young life in these circumstances is truly heartbreaking and our thoughts and prayers are with his friends and family at this extremely difficult time.
“This sad news is in stark contrast to the jovial carnival atmosphere just hours before at the game against Poland.”
Patrick Nelson, the chief executive, of the IFA said: “On behalf of the board, management, players and staff of the Irish Football Association, I would like to express my deep sadness at the tragic death of a Northern Ireland supporter in Nice in the early hours of this morning.
“The thoughts of everyone at the association are with his family and friends at this time.”
Gary McAllister of the Amalgamation of Northern Ireland Supporters Clubs said: “I’m sure that every Northern Ireland fan, both here in France and at home, will be thinking of Darren and his loved ones at this very sad time.”