Police today named the six victims killed and one man still missing after last night's Morecambe Bay helicopter disaster.
The dead were named as pilots Stephen Potton, from Blackpool, and Simon Foddering, from Preston, and passengers Robert Warburton, 60, a married man from Heysham, Lancs, Leslie Ahmed, 48, from South Shields, John Shaw, 51, a married man from Kirkcaldy, Fife, and Alfred Neasham, 57, from Durham.
The missing passenger was named as Keith Smith, from Stockton-on-Tees.
Police said the chances of finding Mr Smith alive are now "slim" although a massive search and rescue launched after the crash is still under way.
All the men were on a routine helicopter flight when it ditched into the sea 500 yards short of the gas rig where it was about to land at around 6.30pm last night, 24 miles out to sea in Morecambe Bay.
The cause of the accident is not yet known.
Detective Superintendent Mick Gradwell, of Lancashire Constabulary, said the helicopter left Blackpool at about 6pm.
It flew to one rig, picked up a number of people, then flew to a second rig and was on its way to a third when it plunged into the sea.
It was 500 yards from the third rig when it "reared to the left" before ditching in the sea.
Three people witnessed the aircraft's horrifying final moments.
Keith Mullett, from helicopter company CHC Scotia, said Mr Potton was the company's chief pilot in the area and described him as "extremely experienced".
Mr Foddering joined the company about a year ago but was also an experienced pilot, he added.
A former neighbour of victim Mr Shaw, from Kirkcaldy, Fife, who asked not to be named, said he was "shocked and saddened" at the news.
He said: "I knew he worked on the rigs. He was an electrical engineer and used to be a miner. I just can't believe this.
"I lived beside him for about 20 years. He moved away a few years ago but this is awful. He has grown-up children, was divorced and has a new partner, Louise.
"I knew there had been an accident but I never thought it would be him. It's terrible."
Although formal identification has yet to take place, the names of the seven men on board have been released.
The families of all those involved in the crash have been informed.
Sam Laidlaw, from gas firm Centrica, said the company was "deeply saddened" by the tragedy.
"Our priority is to provide as much support as we can," he said. "Our thoughts and prayers are with the families at this terrible time."
An investigation by the Air Accident Investigation Board (AAIB) has been launched.
Chief pilot Mr Potton, 51, had been with CHC Scotia for more than 20 years.
Mr Foddering, 33, was a senior first officer, who had been with the company for just over a year but was an experienced pilot in his own right, the helicopter firm said.
At a press conference today at Blackpool police station, Chief Superintendent Russ Weaver said: "The helicopter was on the approach to a gas platform 25 miles off the Lancashire coast.
"It was on a routine flight, moving staff between rigs. As it approached the rig it crashed into the sea.
"The weather was considered normal for the time of year and none of the witnesses have described any unusual events.
"The helicopter went into the sea 500 yards short of the rig with seven people on board.
"An air and sea search commenced and six bodies were recovered from the sea. A seventh person is still missing, but realistically the likelihood of survival of the missing person is now considered to be slim."
Centrica chief executive Mr Laidlaw said the four dead passengers all worked for the firm.
The missing man, Mr Smith, worked for another firm, Costain Petrofac.
Mr Laidlaw added: "We are deeply saddened by the events of last night. We are providing support to the family and friends and colleagues of those who died.
"This is the first major incident to affect our operations in Morecambe Bay since they began 21 years ago."
Coastguard manager Steve Travis said the search for the missing rig worker had been hampered by poor weather conditions and fog, and the current operation was searching a 32 square mile area.
CHC Scotia managing director Mr Mullett said the safety record of the Eurocopter the men were in was "excellent" and there were no concerns over the craft.
He added: "Stephen Potton, the captain, was our chief pilot at Blackpool and had over 20 years' experience.
"Simon Foddering was the senior first officer and, although he only joined us just over a year ago, he was an experienced pilot.
"This was an experienced, capable crew."
No mayday was sent by the craft before it ditched into the sea.
There was "substantial" wreckage after the helicopter went down. The onboard flight data recorder, or black box, has a beacon attached, and investigators are in the process of locating it.
Police would not speculate about the causes of the crash.
Three people on the drilling rig platform witnessed the accident, police said.
Eyewitnesses said they saw the helicopter approach the platform and 500 yards short it veered to the left and crashed into the water.
One of witnesses, who was due to get on board, was left "traumatised and shocked" after seeing co-workers killed.
The people on the platform raised the alarm and two boats were scrambled but the men could not be saved.