An RAF helicopter has caught fire after making a "precautionary landing" in the mountains of Snowdonia.
Emergency services were called to the Yr Aran area as pictures emerged of black smoke rising from a peak.
A Ministry of Defence spokesman said the incident involved a training helicopter and everyone on board was accounted for.
He said: "A Griffin training helicopter safely completed a precautionary landing in Snowdonia this afternoon following a technical issue. Everyone on board exited safely, subsequently the aircraft caught fire."
Six people in total were involved in the training - five military personnel and one civilian.
Five people - four military and one civilian - were in the aircraft, and the sixth person was on the ground.
All of them were safely transported from the landing site.
Yr Aran is a mountain peak on a ridge south of Snowdon, the highest mountain in Wales.
Twitter user Philippa Napper posted a picture showing smoke, writing: "Big fire on peak next to #snowdon Now just black smoke. Accident?"
Huw Price also posted a photograph and wrote: "Think a helicopter has crash-landed on top of mountain across from Snowdon. Huge fire, can see the flames from here."
Chief Inspector Nick Evans from North Wales Police said that just before 1.45pm emergency services attended to reports of a helicopter crash landing in the Yr Aran area.
"The Wales Air Ambulance in partnership with the Welsh Ambulance Service attended the location along with North Wales Police and Mountain Rescue Teams.
"It transpires that an RAF training helicopter from RAF Valley safely completed a precautionary landing in Snowdonia this afternoon following a technical issue.
"All occupants of the aircraft exited safely before the aircraft caught fire," he said.
A Welsh Ambulance Service spokesman said no one needed hospital treatment.
According to the RAF website, the Griffin HT1 is used as an advanced flying-training helicopter at the Defence Helicopter Flying School at RAF Shawbury near Shrewsbury and the Search and Rescue Training Unit at RAF Valley on the island of Anglesey.
As well as pilot training, the Griffin is used for crewman training - "a very important and integral part of multi-crew operations", the website says.
It adds that it is especially useful for procedural instrument-flying training and practising "complex emergency-handling techniques".
The Duke of Cambridge trained at RAF Shawbury and did an advance course on Griffin helicopters.
He served with the search and rescue force while based at RAF Valley in Anglesey.
William served a three-year tour with the SAR and during his time qualified as an operational captain, taking overall control of his Sea King helicopter.
The Duke - known as Flight Lieutenant Wales - flew 156 search and rescue operations, resulting in 149 people being rescued.