A Rolex watch of "extreme sentimental value" was stolen from the Northolt home of an 87-year-old woman.
Cash was also taken by the thief on Thursday (March 15) who allegedly posed as plumber "checking for water leaks" to gain entry to the elderly victim's house.
According to Metropolitan Police the burglary happened when a man in blue overalls knocked on the pensioner's front door at around midday and insisted he come in to check the property for leaks.
He went into the bathroom and the kitchen before leaving at around 12.30pm.
The victim reported the burglary to police when she realised cash had been taken from her purse.
The stolen Rolex was given to the victim in 1979 by her late husband and is of "extreme sentimental value."
Following the burglary the victim is said to feel "very unsafe in her own home and has lost trust in everyone."
Acton CID, Detective Constable, Andrew Vyvyan, from said: "Following this incident, the victim feels very unsafe in her own home and has lost trust in everyone.
"The watch was given to her by her late husband as a present in April 1979, and it's of extreme sentimental value.
"Although the cash was also stolen, it's the watch that we really want to return to the victim."
The alleged thief is described as a white man, aged between 60 to 65 years old and around six foot tall and who spoke in an English accent.
Anyone who may know of the whereabouts of the watch is asked to call Acton CID on 0208 721 7110. Alternatively, Crimestoppers can be contacted anonymously on 0800 555 111.
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