A porpoise found stranded on a Swedish beach in June died of bird flu, the first time the virus has been detected in a porpoise, Sweden's National Veterinary Institute said Wednesday.

"As far as we know this is the first confirmed case in the world of bird flu in a porpoise," veterinarian Elina Thorsson said in a statement.
"It is likely that the porpoise somehow came into contact with infected birds," she said.

The bird flu virus, H5N1, was found in several of its organs.

The virus has also previously been detected in other mammals, including red foxes, otters, lynx and skunks, the institute said.

Europe and North America are currently seeing a vast outbreak of bird flu among wild birds.