An orca has reportedly rammed into a yacht which was sailing from Lerwick to Bergen, The Guardian has reported.
It is believed to be the first such instance of an orca attacking a boat in the North Sea.
Dr Wim Rutter, from the Netherlands, was said to have been sailing solo on Monday when the orca hit the stern of the boat while he was fishing for mackerel.
There have been recent reports of orcas attacking boats in the Strait of Gibraltar and near to Portugal.
The annual Bergen-Shetland race got under way today, with 43 yachts expected to sail into Lerwick – with some arriving tomorrow (Thursday).
They are then due to sail back to Bergen on Sunday.
Organisers of the event have been approached for comment.