Two men died today after apparently being overcome by fumes on a barge, the coastguard said.
A rescue operation was launched after reports that three men were unconscious on a fish farm vessel.
The boat was moored on Loch Creran, near Oban in Argyll, when the alarm was raised.
A Clyde Coastguard spokesman said two of the men had died and a third was being treated in hospital.
The incident happened shortly before noon today.
A Strathclyde Police spokeswoman said: "At 11.50am emergency services were called to a report of an industrial incident involving three men in the Rhugarbh area of Loch Creran.
"Police, coastguard, Oban Lifeboat, RAF air rescue and Strathclyde Fire and Rescue are in attendance.
"It's being treated very seriously".
A spokesman for the Scottish Ambulance Service said three patients were airlifted to Lorn and Isles Hospital in Oban.
A Clyde Coastguard spokesman said: "We believe there were three people who had fallen into the hold of a barge.
"The initial report was that all three were in the tank space of the hold and were unconscious.
"It was thought there was some risk of noxious fumes and there was also a report of two of the men being overcome by fumes and one who was injured.
"One of the men who was recovered was taken to hospital. The other two were fatalities."Reuse content