The health and safety executive is investigating an Orkney scallop boat involved in the dramatic rescue of a diver.
The Fair Morn lost track of Bulgarian diver Ivan Doychev on Wednesday evening after fouling its propeller while checking on another diver working nearby in Scapa Flow.
Mr Doychev drifted away in the tide and was recovered more than 11 hours later off Duncansby Head on the opposite side of the Pentland Firth.
A thorough investigation of the incident is now ongoing and it is understood that inspectors from the Health and Safety Executive (HSE) will travel to Orkney late next week.
It is understood that the boat, based out of St Margaret’s Hope on South Ronaldsay, was of interest to the HSE before Wednesday evening’s incident.
Last night a spokesman for the agency said: “The HSE has been informed of an air and sea search that took place in southern Orkney.
“Inspectors are currently working with Police Scotland and Marine Scotland.”
The boat’s owner Fred Brown spoke after Mr Doychev was rescued about his relief – saying it was “like the world had been lifted off our shoulders” when they received a call the diver had been collected by a Russian sailing vessel.
Mr Doychev, 40, was well equipped and was able to attract the attention of the sailing boat himself by swimming towards it and shouting.
He was initially taken to Caithness General Hospital before being allowed to return to Orkney, where he was lived and worked for almost a year, on Thursday evening.
A large scale search was launched for Mr Doychev, including two coastguard helicopters and three lifeboats from Stromness, Longhope and Thurso.
Mr Doychev put his survival down to not panicking – saying after his rescue “if you panic you drown”.
He added: “I am very appreciative of the coastguard. I could see the choppers and boats. They were far away but I could see them so I knew they were looking for me which kept me going.
“Thanks also to the people that have helped me.”