The fashion designer Nicole Farhi has been robbed at knifepoint outside her £3 million home by a gang thought to be selecting lone women for their money and jewellery.

The French-born designer was grabbed from behind and had a knife put to her throat when she returned to her house in Hampstead, northwest London, last week.

Two men forced her to hand over an £8,000 ring, a watch and foreign currency before fleeing in a small, silver car. Her husband, the playwright Sir David Hare, is believed to have been in the house but was unaware of the attack.

Detectives are trying to establish how the robbers knew that Farhi, 61, would be alone and at her house at 11pm last Thursday, and whether she was selected by the gang specifically.

Farhi’s housekeeper said: “We were all in bed when she came home. It was very distressing for her and she was very traumatised by what happened. She has been to work only once since.”

It is believed that the same two men have been behind several attacks in the area in recent months. Officers from the Camden robbery squad are searching for the men, who are described as black and aged between 25 and 35.

Detective Chief Inspector Steve Burns, from the squad, said: “There have been three incidents over the last three months in Hampstead where lone women have been robbed of their jewellery.”

Farhi, who was born in Nice, trained in fashion design and started her career in Paris before moving to London in the 1970s. She started her own line of sporty clothing in the early 1980s before adding collections of swimwear, shoes, accessories and evening wear. In 2005 she started selling fragrances.

She has been nominated for the British Fashion Awards eight times and, among other awards, won the British Classics award in 1989.

Police are investigating a similar attack carried out by two black men on a 25-year-old woman in Paddington, West London, on Wednesday morning. The woman was on her way to work at 6.30am near Marylebone station when she was grabbed from behind by assailants who tried to steal her bag. She is thought to have struggled and was stabbed in the abdomen. When she regained consciousness she found her bag next to her with its contents intact.

In another attack, less than half a mile from Farhi’s home, a woman was robbed on the doorstep of her friend’s house in Fairhazel Gardens, south Hampstead. The victim, who is also 61, was throttled until she passed out. Two black men wearing balaclavas stole two Tiffany bracelets, a ring, a watch and a purse in the attack on Wednesday last week.

Detective Constable Tony Bellis said: “This was a truly horrific robbery that has left the victim considerably distressed and in shock.”

The next night Farhi was attacked by two men of the same descriptions.

Wendy Bain, who lives in Fairhazel Gardens, said: “People are scared. We were told there have been six of these incidents in this area in the last couple of months.

“We know that these criminals are a highly organised and very professional outfit. I’m incredibly frightened.

People should be aware that even though they are living in a nice area they need to watch out.”

The Metropolitan Police has published guidelines for people who are concerned about their personal safety.

Be careful out there

The Metropolitan Police offers the following advice on personal safety:

— Think ahead and plan your journey, avoiding deserted areas

— Try to avoid walking alone at night and keep to well-lit main roads where possible

— Try to avoid short cuts such as alleyways, waste ground and wooded, bushy areas

— Stay alert: be aware of what is going on around you

— Let someone know where you are going, the route you intend to take and when you expect to return

— Consider investing in a mobile phone. There are various services available for light users

— Try to avoid wearing headphones – your ability to hear traffic, strangers or potential trouble is severely restricted

Source: Metropolitan Police

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