10:24pm UK, Friday May 12, 2006

Police are appealing for witnesses to the fatal stabbing of a woman special constable outside her home in northwest London.

Nisha Patel-Nasri, 29, was off duty when she was attacked late last night in Wembley.

180 police at house stabbing

Police are at the scene

Police believe Mrs Patel-Nasri, who was an unpaid volunteer police officer, was investigating a disturbance on the street.

She was found in her nightclothes covered in blood by neighbours who had heard her screaming.

First aid was given by police and a neighbour before she was taken to Northwick Park Hospital but she was pronounced dead on arrival. She had been stabbed in the leg.

Neighbours said they saw a man in a hoodie running away from the scene of the murder on Sudbury Avenue towards the Harrow Road.

Detective Superintendent Julian Worker told Sky News it was crucial witnesses came forward. Police feel the knifeman is being shielded, he said.

Police added she chased off three men who tried to break into her house on Saturday.  

It is not known if the two incidents were linked but police will be investigating.

Well-known in the area, she had worked as a special for four years and ran her own successful hairdressing business.

Former senior Met officer Roy Ramm called the killing an "absolute tragedy".

Film director Michael Winner, who leads a memorial campaign for slain police officers, blamed the courts and weak Government policies for "encouraging" criminals to carry knives.

A national knife amnesty is being launched in a few weeks.

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