A number of emergency services were called to Dalradian Gold's Camcosy Road site on Friday afternoon after reports that a "person injured them-self inside".
A spokesperson for the fire service said teams from Omagh, Newtownstewart and Belfast were deployed to the mine - just outside Greencastle - at around 2.20pm.
But on arrival at 2.50pm they said staff had told them they were not needed as the man who had been hurt was no longer in the mine.
It is understood he suffered an injury to his leg.
NIFRS said no Fire Service personnel were deployed to the site of the incident, and the Specialist Rescue team on its way from Belfast had been advised to turn around.
"A chap had hurt himself," said NIFRS. "We had no action to take. Whenever we arrived, it had been resolved," said their spokesman.
A spokesperson for the PSNI added: "Just before 2.30pm, police received a report from the NIFRS of a man being injured in the Camco(s)y Road area of Omagh. Police were not required to attend."
Both Dalradian Gold and Northern Ireland Ambulance Service have been contacted for comment.
At this point it is unclear whether the man was taken to hospital to hospital for treatment.