The deaths of two seals with bird flu marks the first time the disease has been found in mammals at a National Trust site, the charity has confirmed. It said influenza of avian origin was detected in two seals at Blakeney Point, Norfolk, after four of the animals were found dead.

Experts have raised fears for the seals at England’s largest colony after four were found to have died after having been infected with bird flu. Government scientists are investigating to find out whether the seals died after scavenging from the corpses of infected birds.

Bird flu has been confirmed at a farm in Devon, the Animal and Plant Health Agency (APHA) has said, meaning all birds on the premises must be culled. The case was confirmed at a commercial poultry business near Teignmouth, Teignbridge.