Oil and gas firm Total may be forced to abandon part of a North Sea well due to an underground leak.
Workers aboard the Elgin B platform discovered the leak while drilling 140 miles off Aberdeen in the Central Graben area.
The Health and Safety Executive has been made aware but Total said the incident is under control.
The leak is believed to have occurred more than two miles below the seabed.
A spokesman said: “Total has encountered difficulties whilst drilling a well on its Central Graben asset.
“The well remains under full control at the surface and the situation is under continuous review.
“Wireline measurements carried out inside the drill string indicate some flow exists within the well which means part of the well may need to be plugged and abandoned.”
Total was fined a record £1.1m following a major gas leak from the Elgin field in 2012.
Lang Banks, director of environmental charity WWF Scotland, said: “This is a worrying development, as this is not the first time Total has had problems at its Elgin-Franklin field.
“Only a few years ago, a leak on its platform complex led to an emergency evacuation and a halt to production for almost a year.
“Protecting staff and the marine environment should always be priority number one for the oil and gas industry.
“Given the previous problems at this site, serious questions need to be asked by the relevant authorities as to what is going on.”