Members of the public should intervene if they see a crime being committed, Jacqui Smith has said.

The Home Secretary said passers-by should not "wade into a fight" but said she hoped Britain was a land where people were "willing to stand up for others".

Her comments came after Conservative Mayor of London Boris Johnson advised teenagers in the capital to "walk away" from trouble rather than risk their lives trying to help.

Ms Smith said: "I would never say: 'Don't get involved'.

"I hope that we don't live in a country where people aren't willing to stand up for others."

She added: "I'm the mum of a teenage son. There is not a parent of a teenager who wouldn't worry about any kid, whatever colour or background, being stabbed."

Speaking earlier this month, Mr Johnson told London's teenagers: "Whatever you do, if you see a fight in the street, don't risk it because someone could have a knife.

"I'm saying to kids: 'Don't get involved, move away'."

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