Gordon Brown joined in a moment of silence as a memorial was unveiled in the city for murdered Bradford police officer Sharon Beshenivsky.

Amid tight security, the Prime Minister and Home Secretary Jacqui Smith were among those who gathered for the poignant ceremony at the spot where the 38-year-old policewoman was fatally shot.

Film director Michael Winner was also there as chairman of the Police Memorial Trust which made the stone possible.

Mother-of-three PC Beshenivsky died after being shot once in the chest outside the Universal Express travel agency in Morley Street when she and a colleague attended an armed robbery in November 2005.

Yesterday a sea of flowers once again were lain outside the travel agents, hidden by black sheeting, in her memory as family, friends and colleagues of PC Beshenivsky paid tribute.

The memorial stone bore the words "Here fell Sharon Beshenivsky”, with the date of her death, November 18, 2005, and the badge of West Yorkshire Police carved in gold inlay.

Gordon Brown pledged Sharon would never be forgotten and paid his own tribute to all police officers around the country doing their duty.

Paying tribute, the Prime Minister said: "We are gathered here because of the importance of today, to celebrate the dedication, the service, the professionalism and, most of all, the courage of a young police officer who gave her life serving the community, gave her life doing what she loved doing, gave her life doing what police officers have to do every day."

Mr Brown added: "We want to say that we will never forget the life and the sacrifice of PC Sharon Beshenivsky."

Mr Brown described PC Beshenivsky as "a wonderful wife, a wonderful mother, a wonderful servant of the community, a courageous woman".

Paul Beshenivsky described how his wife's death had affected the family.

He said: "On November 18, 2005 our family life changed forever.

"The nation saw the tragic loss of yet another police officer but we, her family, felt the intense pain and suffering that only comes from losing someone you love."

After giving his speech, Mr Beshenivsky introduced his 10-year-old son, also called Paul, who said: "I would like to thank Michael Winner for organising this event for my mummy and everyone else who is here today. I know she would be very proud."

Mr Winner paid tribute to PC Beshenivsky's heroism that day and also praised police officers across the country.

He described the work of the police as an "ongoing war" and added: "We owe the people who fight that war enormous gratitude."