Health experts are trying to establish whether dozens of people taken ill on board a cruise ship are suffering from the norovirus.
Both passengers and crew are showing suspected symptoms of the vomiting bug on board the Transocean Tours-operated Marco Polo, which is berthed in Invergordon, Easter Ross.
A 74-year-old man suffered a fatal heart attack on board the ship on Monday, but his death was unrelated to the bug, the ship's operator said.