Three men have died after an accident on a gas rig standby vessel in the North Sea, the boat's operators say.
The Viking Islay is an emergency response and rescue vessel
Vroon Offshore Services said they died on the Viking Islay in the BP Amethyst gas field off the East Yorkshire coast.
The men were named as Finlay MacFadyen, 46, from Aberdeen, Robert O'Brien, 59, from Leven in Fife, and Robert Ebertowski, 40, from Gydnia, Poland.
The Aberdeen-based company said they were securing an anchor chain in the boat's bow when the accident happened.
Mr MacFadyen and Mr O'Brien, both coxswains, and boatman Mr Ebertowski were on board the vessel 25 miles (40km) off the East Yorkshire coast when they were involved in the incident at 0100 BST on Sunday, the company said.
They were taken to Hull Royal Infirmary by a Sea King helicopter based at RAF Leconfield, East Yorkshire, but died of their injuries.
The remaining nine crew members were safe and well, Vroon Offshore Services confirmed.
The Viking Islay, a 53-metre emergency response and rescue vessel, was supporting the Ensco 92 drilling rig on BP's Amethyst field when the accident happened.
The company said it had now been returned to the Humber port of Immingham where a full investigation would be carried out by the Marine Accident Investigation Branch.
Graham Philip, chief executive of Vroon Offshore Services, said: "This is a tragic incident, the details of which are still unclear.
"However, we are doing all we can to find out what happened and will co-operate with all relevant authorities to carry out a full investigation.
"Our thoughts currently lie with the family and friends of the men who have tragically lost their lives."
Vroon Offshore Services owns and operates 32 vessels.