Up to four people were feared dead today in a helicopter crash in Northern Ireland.
It is believed the craft came down in the Mourne Mountains in Co Down.
Police, mountain rescue teams and coastguards were involved in a search operation after reports of a crash at 4pm yesterday.
The site is thought to be the Leitrim Lodge picnic area near Hilltown.
Police said the exact nature of injuries was still being established.
Members of the public spotted a helicopter in the area and believed its engine sounded abnormally loud.
The emergency services later received reports that an aircraft was in difficulties.
Chartered helicopter flights in the region are a relatively common sight, with golfing groups and wedding parties known to have used them in the past. There was no immediate confirmation of the nature of yesterday's flight.
The Mournes area is internationally renowned for its picturesque scenery. The mountain range, set on the coastline of south Co Down, is designated as an area of outstanding natural beauty.
The highest mountain in the range, Slieve Donard, is nearly 3,000 feet high.
But changeable weather patterns along the coast and the presence of the mountains have led to tragedy in the past.
In June last year three men were killed when their light aircraft crashed into a field near a private landing strip at Kilkeel, Co Down.
The pilot Hugh McKnight, who was a 53-year-old former police officer, was returning from the TT races in the Isle of Man with Andrew Burden and Stephen Annett, both aged 24.
The coastal community has also been hit by fishing tragedies in recent years.
The death of four police officers killed when their police 4x4 vehicle crashed on a winding road near Kilkeel in November 2008 also shocked the local community.
Sinn Fein MP for Fermanagh-South Tyrone Michelle Gildernew said the helicopter was believed to have taken off from St Angelo Airport in Enniskillen, in her constituency.
She said: "This is a shocking and tragic accident and my sympathies go out at this time to the families of those who have lost their lives. It is believed that the flight originated at St Angelo Airport in Enniskillen and the shock of this accident has been felt by people right across Co Down and Co Fermanagh."
Democratic Unionist representative for the area Jim Wells said the local community was shocked and feared the worst.
"South Down has been hit by tragedies of this type over the years," he said.
"It looks like we have had another accident which looks like it has led to multiple deaths."
South Down MP Margaret Ritchie said the area was finding it difficult to come to terms with the news.
"On behalf of the people of South Down and those I represent, I offer my deepest and most heartfelt sympathies to the families of the bereaved at this most tragic time," she said.
"This is a terrible reality, almost too difficult to comprehend and we can only imagine it is all too real and awful for the families bereaved.
"I'm in no doubt that the people of South Down will stand in solidarity with those that have lost loved ones and the survivors of this most terrible tragedy.
"Sincere thanks and appreciation must go to all involved in the rescue and recovery operation which could take a little time because darkness has now descended."
The MP added: "Anybody with knowledge of the local landscape should give it to the police and emergency to help the rescue operation and lessen the anxieties and distress for all involved."
Ulster Unionist Party representative Danny Kennedy said: "I was shocked to hear about the crash and am deeply concerned for the people involved.
"While there are no details as yet my thoughts and prayers are with the passengers and their families who must be deeply worried at this time."Reuse content