The number of people killed after a helicopter went down near Sumburgh on Friday has risen to four, police have confirmed.
They were Duncan Munro,46, from Bishop Auckland; Sarah Darnley, 45, from Elgin; Gary McCrossan, 59, from Inverness and George Allison, 57 from Winchester.
Three bodies have been recovered and work is ongoing to recover the fourth.
Police Scotland assistant chief constable Malcolm Graham said: “Our sympathies are very much with the families of those affected at this difficult time. All families have been informed and specially-trained family liaison officers are currently providing them with support.
“This incident has resulted in a large-scale response from a number of different agencies who have worked closely together to deliver a swift rescue operation. We have been able to deploy a number of officers with specialist disciplines from across Police Scotland to assist with the operation.
“We will now be carrying out an investigation to establish the circumstances in due course.”
Eighteen people were on board the CHC helicopter – 16 passengers and two crew – which went down south of Garths Ness at around 6.30pm on Friday. Fourteen people were taken to the Gilbert Bain Hospital in Lerwick for treatment, including the two crew members.
Five were discharged and nine detained overnight either for observation or suffering from exposure.
Isles MSP Tavish Scott added his voice to those demanding to know how the incident happened.
He said there had been repeated serious and fatal crashes involving Super Puma helicopters.
“The operators are right to ground the entire fleet,” Mr Scott said. “But there are now serious questions about why the Super Puma had been cleared to fly given its tragic record in recent years.
“People across Shetland are thinking today of those lost and the incalculable impact on their families. I also want to thank the emergency services including the local lifeboats, auxiliary coastguard teams and so many others for the professionalism of the rescue operation.”
Mr Scott said the oil industry must ask “detailed questions about moving people to oil and gas rigs in the North Sea and West of Shetland”.
He added: “The shortest helicopter journey must surely be the best option with people being flown to the nearest airport by fixed wing aircraft. Men and women who work offshore must have confidence in the aircraft types they are being asked to fly in. I can’t see how that can include the Super Puma.”