The oil company Shell has said it shut down a platform in the North Sea after a gas leak.
The leak was detected on Friday on the Brent Charlie platform, 115 miles north-east of Shetland.
Production has been stopped and 31 non-essential personnel are being flown home as a precaution. Shell said the leak had been stopped and an investigation was under way.
The Brent Charlie had 176 people on board at the time.
A Shell spokeswoman said: “Following a gas detection alarm, production was shut down and the platform called to muster. The source of the leak has been safely detected and isolated, and a full investigation into the cause will be completed.
“All 176 personnel on board have been accounted for and a precautionary partial downman of 31 non-essential personnel is under way.
“Relevant authorities have been informed.”
The company said the leak was discovered on the platform above sea level.
No details have been given of the amount of gas which escaped but Shell said the leak was isolated on the same day that it was detected.
A spokeswoman insisted there has been no impact to the marine environment.
The Brent Charlie platform acts as a hub from other platforms to the pipeline which carries oil to the shore.
But Shell said no other platforms have been affected by the shutdown.