Another dolphin has been found dead after mistakenly swimming down the River Great Ouse near King's Lynn.

The pair, a mother and calf, were spotted in the river last week near Cross Bank Road.

READ MORE: Dolphin spotted in Norfolk river dies days later

They carried on upstream, where the calf got into difficulties after becoming trapped in reeds on the edge of the New Bedford River, which runs off the Great Ouse.

Experts from the British Divers Marine Life Rescue (BDMLR) were called at 7.30pm on September 2 to assist the dolphin, near to the fenland village of Pymoor, in Cambridgeshire - around 45 miles from the coast.

The calf died from its injuries, with experts from the British Divers Marine Life Rescue left trying to track the surviving mother.

But she has now been found in the same river by Robert Deaville from the UK Cetacean Strandings Investigation Programme (CSIP) who spotted the dolphin floating in the water on Monday (September 4).

He said: "Unfortunately, the second dolphin sighted in the Great Ouse was found floating dead in the river while I was en route to another stranding."

The CSIP will now carry out a post-mortem examination to determine the cause of death.