Police divers have been called in to search for a grandmother who has been missing in Australia for almost a month.

Rita Braidwood, 76, from Hove, has not been seen since March 26 when she was spotted near a Sydney supermarket, 13 days into a holiday.

A string of emotional TV appeals by family members have not yielded any firm clues to the mother-of-nine's whereabouts, although a number of unconfirmed sightings are still being investigated.

Detectives confirmed they would today bring in divers to search lakes and waterways in the south of the city.

Mrs Braidwood was shopping with Australian relatives when she disappeared.

Security camera footage from the supermarket showed her walking towards a railway station.

Her son Stephen Braidwood, from south London, said: "We are very worried. She occasionally loses track of time but that's a side effect of an illness she has.

"She had nothing but a small amount of money on her and she didn't have her credit cards or passport. We think she may have got confused."

He said the family was growing more worried about Mrs Braidwood's safety and feared if she did not take medication for a kidney infection she might become increasingly disorientated.

One of her daughters, Gillian Sofatzis, said: "Our mother is not in the best of health and we are concerned her condition might have deteriorated and she could be confused, wandering around and not sure of where she is or that we are looking for her."