TWO men are believed to have been involved in the attack that left a volunteer policewoman bleeding to death outside her front door, police said last night.

One man was seen walking calmly away as Nisha Patel-Nasri screamed for help after being stabbed in the leg while confronting what she thought were burglars.

The second suspect was walking in the opposite direction from a hooded man who, witnesses said, ran off along Sudbury Avenue, Wembley, northwest London.

Mrs Patel-Nasri, 29, was off-duty and had just celebrated her third wedding anniversary with her husband, Fadi, when she heard a disturbance outside her house and went to investigate.

Less than a week before she had challenged three young black men who appeared to be trying to break into her home.

Detective Superintendent Julian Worker, who is leading the murder inquiry, said that he regarded both men as suspects.

“When someone is seen walking away, quite cool and collected, while a woman is screaming out then obviously we have to view him as a suspect,” said Mr Worker.

“The truth of the matter is Nisha is screaming and he doesn’t look back.

“We are anxious to trace both men and anyone who saw them around midnight on Thursday, in the period before then and in the aftermath of the incident.”

Mrs Patel-Nasri suffered rapid and huge blood loss when the single stab wound severed her femoral artery. Detectives believe that the clothing of at least one of the suspects will have been heavily bloodstained.

Her husband, who runs a limousine hire business from home, joined the police in appealing for help in finding his wife’s killers.

Mr Nasri, 32, said: “Obviously, someone has got a guilty conscience. They shall be worrying about what they have done, or be shocked. Or maybe it was an accident or mistake, or whatever.

“We know that someone has to know something about who lives around them. A neighbour may have seen some blood, or someone acting suspiciously or nervously. It might not be important, but just give us a call and let us know.”

Mr Nasri was the target of threats this year after a business disagreement. But police sources said that they did not think that the dispute was connected to his wife’s murder.

The couple had celebrated their anniversary by having dinner together. Mrs PatelNasri, who had her own hairdressing business, then told her husband to go off and enjoy a game of snooker.

She was alone and in her nightclothes when she heard noises outside and went to investigate.

Neighbours were alerted when they heard “a dreadful scream” and looked out to see Mrs Patel-Nasri waving a torch and stumbling before falling to the pavement.

Katen Patel, the dead woman’s brother, cancelled his wedding ceremony this weekend as he and his family tried to come to terms with their loss. He said that he had tried hard to dissuade her from becoming a special constable because of the “very, very dangerous” work involved.

Mr Patel said: “She wanted to do it: she got in. She was very proud, and she did it free of charge. She didn’t take a single penny . . . she did it out of the goodness of her heart to help people and catch people.

“Some people are born with bad blood inside of them, and it’s other people who have to try and stop it, and she was one of those people that wanted to stop crime, which is why she wanted to become a special.”

Officers and staff from Wembley police station, where Mrs Patel-Nasri worked, observed a minute’s silence and laid a wreath at the spot where she died.

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