Home Secretary David Blunkett has promised that the killer of Nottinghamshire jeweller, Marian Bates, will be brought to justice.
Marian Bates died protecting her daughter
Mrs Bates, who was 64, died when she was shot by armed robbers as she shielded her daughter at her shop in Arnold on Tuesday.
Mr Blunkett, who spoke at the Labour conference on Thursday about the government's record on law and order, pledged to tackle gun crime.
After hearing Mr Blunkett's remarks, Mrs Bates' daughters Naomi and Xanthe challenged the government to "put their money where their mouth is".
Mr Blunkett said: "I think it's a terrible tragedy that Marian Bates should have been shot.
"My heart goes out to her family."
Xanthe Bates said: "He needs policemen that are approachable on the streets of
Britain... we should not have to live like this.
"My dad made several reports in the local papers over the past few years about how police should be back on our streets."
Mr Blunkett said the new head of the Home Office's Police Standards Unit, Paul Evans, who is coming from Boston in the United States, would use his "phenomenal" record in combating gun and organised crime to beat the criminals.
He said: "I want the experience of the Metropolitan Police in London with Operation Trident dealing with gang warfare, guns and drugs, to be spread across the country.
"If we can do that, I think we can take these people on and we can beat them."
Mrs Bates was killed in front of her daughter Xanthe and her husband Victor who were both badly beaten during the raid.
Xanthe, 34, also appealed for help in finding who shot her mother.
"Someone knows who did this. Their mother might know, or their girlfriend."
She said: "There's someone's son or brother who has done this to our family.
Detectives are reviewing CCTV tapes from cameras in the Time Centre, in Front Street.
Mrs Bate's husband of 42 years, Victor, 64, is being comforted by friends and relatives at the family home in Ravenshead, Nottinghamshire.