Rescuers searching for a humpback whale which became entangled in rope believe it may have escaped.
The search was called off after there were no further sightings of the mammal off the coast of Shetland.
The Scottish SPCA, which was involved in the search, said it assumed the whale has broken free, though it is also possible it may have died.
The animal welfare charity and Scottish Natural Heritage launched a rescue operation near the bay of Orra Wick on the north east side of Shetland after coastguards received reports of a whale in difficulty at 9.10am.
It had become entangled in a creel line, a rope attached to cages on the seabed used to catch lobsters and crabs.
A four-strong team of expert divers from British Divers Marine Life Rescue from East Sussex flew up to join the search when it resumed.
Rescuers combed the area but could find no trace of the 25ft whale and the operation was called off.
Scottish SPCA senior inspector Ron Patterson said: "Further to Thursday's sightings of a humpback whale trapped by fishing creels and buoys near Vidlin off the coast of Shetland, it would appear that the whale has now moved on.
"We have been scouring the waters around the area since 7am and there have been no further sightings of the whale, so we are assuming that the whale may have escaped and is now swimming freely, although there is a chance that it may have died. We can't say for certain exactly what has happened to the whale yet but it could surface again."
He asked anyone who spots a whale near the shoreline to call its Animal Helpline on 03000 999 999 or the Shetland Wildlife Rescue Unit on 01595 840 321.