They were removed from the beach amid fears for their welfare, after being abandoned by their mother.

Now they have returned to the same stretch of coast, with an impressive status as world firsts.

This pair are thought to be the world's first recorded instance of wild-born twin grey seal pups.

The brother and sister – named R2-D2 and C-3PO, after the Star Wars characters – were released back onto the beach at Horsey Gap in Norfolk yesterday, having spent four months being cared for at the RSPCA centre at East Winch, near King's Lynn.

They were taken there after being found alone in the sand dunes by the members of the Friends of Horsey Seals group.

It is believed the pair were abandoned by their mother after people disturbed her.

The volunteers suspected they might be twins – and DNA tests conducted while they were being treated confirmed this.

Alison Charles, manager at RSPCA East Winch, said: 'C-3PO and R2-D2 were under three weeks old when they came in and they still had their white lanugo coats.

'They weighed 24kg and 22kg respectively, so their mum had done a very good job of feeding them up to that point. We fed them a fish soup mixture every three hours via a stomach tube when they arrived.'

The seals were loaded onto a trailer at RSPCA East Winch at 8am, arriving at Horsey Gap car park at 10am, before being moved in two kennels over the dunes to the beach to be released.

RSPCA East Winch has had 66 other grey seal pups in the hospital this pupping season, and currently has 50 in care.

Are you caring for an abandoned animal? Email david.bale2@archant.co.uk