Police received the report shortly after 11am.
The Health and Safety executive have been informed and are now taking the lead.
Brian Og Maguire had represented his county at all levels and was a member of Peter Canavan's senior squad that won promotion to Division Three last year.
He represented Ireland at U17 in Internationals Rules against Australia and was captain of the Lisnaskea Emmetts team that won the All-Ireland Intermediate Football championship in Croke Park in February 2011.
Only last week he helped the Emmetts secure their place in the final of the Fermanagh Senior Championship for the first time since 1996.
Speaking to the Impartial Reporter this week Brian had talked of the "buzz" in Lisnaksea in advance of the final but unfortunately that excitement has turned to grief and stunned disbelief.
His stunned friends and team-mates have been issuing hundreds of messages of sympathy on social networks twitter and facebook.
Team-mate Niall McElroy summed up the feeling. @niall_mc1 Can't take this in!! #RIPOgie
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