A light aircraft crashed on a mountainside in Co Fermanagh tonight, police said.
Fire and ambulance crews were alerted after smoke and flames were spotted.
Police said the crash happened at Benaughlin Mountain near Kinawley.
There were no immediate reports of casualties, an RUC spokeswoman said.
A Northern Ireland Ambulance Service spokesman said two crews sent to the suspected air crash had been unable to reach the scene due to difficult terrain.
"Our crews have gone as far as they can by road, and they can see smoke and fire from a distance," he said.
"They are talking about getting helicopters, if necessary, to get the paramedics to the scene."
The delay in reaching the scene meant the emergency services were still unable to confirm whether there had been any causalities.