The seals are infected with the fatal distemper virus.

More than 100 have already been taken at the Royal Society for the Prevention of Cruelty to Animals' hospital at East Winch in Norfolk.

About 800 others have been washed up dead.

An emergency number has been launched to deal with the problem of dead and dying seals on the region's beaches.

Special number

Instead of calling 999 people are asked to ring 0871 244 999 a special number set up by the Department for Environment, Food and Rural Affairs.

Paul Jepson, of the Institute of Zoology , said it was important to know how many seals are affected by the distemper virus epidemic.

He said the institute would be using the details people give them to help find out more about the disease.

"We ask everybody - members of the public, local authorities and wildlife trusts - to report dead seals to us in the first instance.

Wiped out

"We also want to monitor every seal colony, both common and grey, in the United Kingdom."

The Wash is home to the largest population of common seals in England.

The Phocine Distemper Virus (PDV) attacks the seals' nervous systems.

The seal hospital in East Winch was set up after the disease wiped out about 60% of the common seal population in 1988 .