A FORMER Merchant Navy officer left heartbroken after fraudsters raided his late wife's jewellery box has urged pensioners to be on their guard.

Derek Dams, of Rostrevor Gardens, Norwood Green, thought he was doing his Christian duty when he welcomed a young lady into his home last month.

But she and an accomplice abused the 70-year-old's trust to steal more than 20 treasured trinkets belonging to his late wife Margaret.

Their haul included the couple's diamond ship-shaped engagement ring, a pendant with two photos of Margaret and her ruby 40th anniversary ring.

Margaret, who worked as a translator for Rolls Royce, was severely disabled with multiple sclerosis for most of her life.

She died at West Middlesex Hospital on July 26, 2006, aged 68 - four days after celebrating her 43rd wedding anniversary.

Mr Dams described her as a very cheerful woman who would always ask after others despite often being in great pain due to her condition.

"I'm just pleased she wasn't around when this happened because I think the shock would have killed her," he said.

"What worries me is that these people are still out there and other elderly residents could fall into their trap."

The woman knocked at Mr Dam's door on April 5 at about 4.30pm and asked for a pen and paper to leave a note for a neighbour.

But while she kept him talking a male accomplice ransacked the pensioner's bedroom, smashing open his father's 70-year-old deed box and pocketing the jewellery.

Mr Dams, who worships at Our Lady Queen of Apostles Church in Heston, said the pair were in and out within 10 minutes.

"I should have known better, being a naval man, but as a Christian I was trying to help a young woman," he added.

The crooks remain on the loose but police have issued e-fits.

Anyone with information is asked to call DC Colin McLoughlin on 020 8247 5940.