A North Sea oil platform has been shut down and workers taken off, following a subsea structural inspection.
EnQuest said it evacuated the Thistle platform, about 125 miles (201km) north-east of Shetland, in a precautionary move on Monday evening.
The company said 115 personnel were transferred to a nearby platform by helicopter.
The coastguard said its helicopter and two from the Norwegian offshore sector were involved.
Coastguards were made aware of the situation at about 18:30.
An EnQuest spokeswoman said: “EnQuest can confirm it has proactively down-manned the Thistle Platform today in a precautionary move following a preliminary subsea structural inspection today.
“The platform has been safely shut down in accordance with planned procedures.
“EnQuest is liaising with all relevant authorities including the Maritime and Coastguard Agency.”
Jake Molloy, from the RMT union, described the evacuation as “a very unusual set of circumstances”.
He told the BBC’s Good Morning Scotland programme: “You don’t shut a platform down and remove over 100 people if you haven’t got concerns.
“For structural integrity reasons this is only the second time that I can remember in 40 years.
“The last one was the Ninian South pending the Beast from the East arriving.
“This is quite serious, there’s no storms, there’s no significant weather problems. They’ve clearly found an issue which needs further investigation and they’ve thought it necessary to take a precautionary down-man as they call it.”