Four people who died when the helicopter ferrying them from an oil rig ditched into the sea off the Shetland Islands have been named.

They were Sarah Darnley, 45, from Elgin; Gary McCrossan, 59, from Inverness; Duncan Munro, 46, from Bishop Auckland and George Allison, 57, from Winchester.

Three bodies have been recovered so far with police confirming 14 others aboard were rescued and taken with varying injuries to hospital in the islands' capital Lerwick.

The Super Puma L2 aircraft went down at 6.20pm last night, around 3km west of Sumburgh airport as it was returning to Shetland from the Borgsten Dolphin platform in the North Sea.

Reports say the helicopter suffered a sudden catastrophic loss of power. 

The RNLI, who were involved in the recovery overnight, released this footage of the operation. 

The crash of the Super Puma L2 helicopter, made by EADS unit Eurocopter, is the fourth North Sea oil industry-related incident involving different models of the widely-used aircraft since 2009. 

It was operated by CHC Helicopter for French oil major Total, a CHC spokesman said.

CHC said it would carry out an investigation with the UK's Air Accident Investigation Branch. 

It has temporarily suspended its Super Puma L2 flights worldwide and all flights by its UK operations. 

All 14 passengers and two crew died in April 2009 when a Bond- operated Super Puma crashed off Peterhead on the east coast of Scotland on its way back from BP's Millier oil platform.

Last year the crew of a Super Puma helicopter ditched the aircraft in the North Sea after a gearbox failure.

All 19 aboard another Super Puma helicopter were rescued after it ditched during a flight from Aberdeen to the West Phoenix rig, west of Shetland.