A ferry which ran aground, leading to the evacuation of 60 passengers, has been refloated and towed to its berth.
The MV Pentalina will now be surveyed to establish the extent of any damage and monitored for pollution, the coastguard said.
RNLI vessels went to the scene after the vessel issued a mayday message off Orkney on Saturday night.
Pentland Ferries said smoke was detected in the engine room before the Pentalina became grounded off the village of St Margaret’s Hope.
It is understood eight crew members have remained on the vessel to help manage the situation.
A coastguard spokesman said on Sunday: “The MV Pentalina was refloated at approximately 5.30am today after a tow was established by a tug whose services were acquired by Pentland Ferries.
“The Pentalina was brought alongside its berth in St Margaret’s Hope a short while later. HM Coastguard’s emergency towing vessel MV Ievoli Black observed the operation, alongside counter-pollution officers, and reported that there were no signs of pollution.
“The vessel will be surveyed later today to establish the extent of any damage, while the harbour master will continue to monitor for pollution. The MAIB (Marine Accident Investigation Branch) has also been informed.”
Coastguard teams from St Margaret’s Hope, Stromness and Kirkwall and the Stromness and Longhope RNLI boats were involved in the rescue operation after the mayday call at around 7.30pm on Saturday.
The coastguard said all passengers have been reported safe and well.
The Pentalina returned to service earlier this week to allow another ferry, the MV Alfred, to service CalMac routes on the west coast of Scotland.
A statement from Pentland Ferries on Saturday evening said smoke was detected in the engine room before the vessel grounded, adding: “The safety of our passengers is, of course, our first priority.”
An RMT union spokesman said: “A thorough investigation will be needed to establish how this major incident aboard the Pentland Ferries vessel occurred.”
Local politicians are calling for answers from the Scottish Government over what the incident means for ferry users in Orkney.
Transport Scotland said the current priority is for Pentland Ferries to assess the condition of the vessel and any next steps to determine whether there will be any loss of services on the Pentland Firth.
It said any further actions to support capacity to Orkney will be considered in due course.
Scottish Conservative Highlands and Islands MSP Jamie Halcro Johnston, who is from Orkney, said the incident exposes the “pitiful lack of resilience in Scotland’s ferry network”.
Worrying reports from @The_Orcadian that the MV Pentalina has run aground. This is the boat which has been brought back into service to allow CalMac to charter the MV Alfred on the west coast routes. Hoping crew and passengers are OK, and everyone is able to get off safely. pic.twitter.com/0IBJyltGpu
— Jamie Halcro Johnston MSP (@jhalcrojohnston) April 29, 2023
He said: “The Pentalina was only summoned back into action this week because the MV Alfred had to be seconded from Pentland Ferries to help plug gaps in the ageing, unreliable CalMac fleet.
“While it will be important to know just how this incident came about, my immediate concern is for what this means for Orkney and how long this vital link for our islands will be severed.
“There are a number of questions the Scottish Government needs to answer, including whether the £9 million agreement between CalMac and Pentland Ferries allows for the MV Alfred to be recalled to Orkney early, or if the Alfred will stay on the west coast and Orkney will be left without a key service.”
Orkney MSP Liam McArthur said there are important questions for the Maritime and Coastguard Agency (MCA) to answer, as he said it had recently inspected and certified the Pentalina as fit for service.
He added: “Answers are required too from the Scottish Government whose failure to procure new ferries in a timely fashion has left services both in the north and on the west coast extremely vulnerable. As a result islanders and island communities are left paying the price.”
An MCA spokesperson said: “The Maritime and Coastguard Agency, in conjunction with the vessel’s classification society, completed surveys on the vessel Pentalina on April 18 and issued a passenger ship safety certificate; at this time the vessel met the standards required for issue of this certificate.
“Surveyors from the MCA will be attending the vessel today (Sunday) in St Margaret’s Hope to undertake initial fact-finding to establish the cause and circumstances surrounding the incident which occurred on the evening of April 29.
“While the facts haven’t been established yet, initial reports from the operator point to the cause of the grounding being a sudden mechanical failure.”
A Transport Scotland spokesman said: “Ministers were quickly made aware of the incident involving the MV Pentalina and kept informed of developments throughout the night.
“We were relieved that all passengers and crew are safe and that arrangements were made to support passengers with onward travel.
“We would also like to express our appreciation to all those involved in the evacuation, including RNLI crews and other emergency services.”
