Search teams looking for a Fife fishing boat missing in the North Sea have found a life raft and debris.
The Meridian went missing in the North Sea
The Norwegian Coastguard said that there were no identifying marks on the debris, but it was found close to the area where the boat had been.
The alarm was raised when staff at RAF Kinloss picked up a distress call at 2200 BST on Thursday from the Meridian, which is registered in Kirkcaldy.
Three of the crew are from Anstruther and the fourth is from Aberdeen.
Aberdeen Coastguard said bits of debris such as buckets, fishing equipment and boots were discovered by a search team in the area.
The signal was broadcast from a location in Norwegian waters 160 miles east of Aberdeen.
An RAF Nimrod Search and Rescue aircraft was sent from Kinloss, along with a Sea King rescue helicopter.
Two helicopters and up to five vessels on the surface are also involved in the search
Three other fishing boats have joined the search, which is being carried out in storm force 10 conditions with winds gusting up to 80mph.
The vessel, contracted by Talisman Energy (UK) Limited, was involved in guard duty around North Sea pipelines - making sure other vessels do not stray too close.
The Meridian had two life rafts on board and the crew were kitted out in survival gear.
A second Sea King from RAF Boulmer in Northumberland was scrambled at 0500 BST.
Michael Mulford, from the Rescue Co-ordination Centre at RAF Kinloss, said the conditions which had raged through the night were beginning to abate.
The boat was operating around oil platforms in the North Sea
He said: "We knew about the life raft in the early hours of the morning and there was a strong smell of diesel.
"Debris is a difficult one because there is debris bobbing all over the North Sea, but if the Norwegians are confident that is the source, then certainly it does point inexorably to the conclusion you never want when you set out on a search and rescue.
"As each hour goes by you have to be realistic about the chances of anyone surviving that long.
"You can survive for many hours in a life raft but it is very unpleasant because it bobs and moves around, but at least you know you will be spotted from the air because these things are designed and coloured for this purpose."
'Extremely serious situation'
Bertie Armstrong, chief executive of the Scottish Fishermen's Federation, said: "We're all sitting on our hands desperately waiting for news while the full might of maritime search and rescue is applied.
"The missing white fish boat is a member of one of our eight associations. There are a number of families with their hearts in their mouths right now hoping beyond hope.
"There's absolutely no doubt that we have an extremely serious situation here.
"If a boat has been missing for this number of hours in such horrendous conditions the outlook is bleak, it would be daft to say otherwise."
Mr Armstrong said there were up to 200 other fishing boats at any one time in that part of the North Sea searching for haddock or prawns.
Liberal Democrat leader Sir Menzies Campbell, who is MP for north east Fife, said: "At the moment the whole community is praying these men will be found safe."