The RNLI said that its lifeboats have been stood down and are returning to their home ports. It is understood that air and coastal searches are continuing.
There has been no sign of the eight-strong crew since the Cypriot-registered Cemfjord was first spotted by a passing ferry on Saturday.
The 83-metre cement carrier, which had been bound for Runcorn, Cheshire, on the west coast of the UK, sank below the water earlier this afternoon.
Susan Todd, Marine Coastguard Agency watch manager said: “The only thing that’s been recovered that’s notable is one of the rescue boats which we do believe comes from the ship itself.
“It was located yesterday on one of the Orkney islands, although it was upturned and showed no recent signs of occupancy. That’s drifted a few miles from the original incident position.”
German shipping company Brise of Hamburg, which manages the 30-year-old ship, confirmed that there were eight people on board, adding that there had been no distress call.
An inflatable boat recovered by a search team on shore in Orkney. Coastguard ‘do believe’ it came from the Cemfjord. pic.twitter.com/edu4MeGaRv