A five-week amnesty aimed at tackling knife crime across Britain - the first of its kind in a decade - has begun.
It is the first national knife amnesty for more than a decade
Until 30 June people can hand in knives at police stations in England, Scotland and Wales without fear of penalty.
But police have warned that once the amnesty is over, tough action will be taken on those found armed with knives.
However, some families of victims of knife crime have questioned the effectiveness of an amnesty, calling instead for tougher sentencing.
The initiative - which is running alongside a three-week campaign in Northern Ireland - comes amid growing concern at the level of knife crime in the wake of a series of fatal stabbings across the country.
Last week, 15-year-old Kiyan Prince died from a stab wound after being attacked outside his school in Edgware, north London.
Of 820 homicides in 2004/05, 236 (29%) were killed with sharp instrument
This was most common method of killing
Knives were used in 6% of all violent crime 2004/05
Source: Home Office
Figures relate to England & Wales
And earlier this year, 18-year-old Christopher Alaneme was fatally stabbed in Sheerness, Kent.
Speaking in the Commons, Prime Minister Tony Blair said the amnesty was part of a range of proposals to tackle knife crime.
These included adding a range of knives to the offensive weapons list, giving teachers powers to search students and increasing the legal age at which knives can be bought from 16 to 18.
"Where a child is threatened in any way, this will constitute an aggravating factor," he said.
The government would "do everything we can" to stop young people "getting into a knife and gun culture that is not just appalling for its victims and the people who suffer that violence but actually does nothing for the lives of those engaged in it", he added.
During the amnesty, secure bins are being placed in public reception areas of most police stations in an effort to encourage people to hand in their weapons.
Some police forces may also leave bins in churches, supermarkets, schools and youth clubs.
Police are also running a campaign to teach people about the dangers of carrying weapons.
In 1995, 40,000 weapons were handed over during a similar amnesty launched after head teacher Philip Lawrence was stabbed to death outside his school in west London.
Figures also show in the year following a month-long amnesty in Scotland in 1993, murders fell by 26%, attempted murder 19% and offensive weapons possession by 23%.
Anyone found carrying an offensive weapon in a public place after the amnesty could be imprisoned for up to six months and receive a £5,000 fine.
Norman Brennan, director of the Victims of Crime Trust, questioned whether it was just a public relations exercise.
Philip Lawrence's widow Frances, however, said she hoped the amnesty would make people think again about carrying knives.
She told BBC Radio 4's Today programme: "It's greater value is the symbolic one in that it will focus people's minds on the issue and it could, for instance, open up the debate in families for instance, where people may have an uneasy feeling perhaps that their son is going off carrying a knife."