The Conservatives have criticised the government's plans to tackle gun crime as "feeble".
Nick Herbert, the Tory spokesman on justice, dismissed proposals for "drop-off zones" where people can hand in guns or offer tip-offs anonymously.
He told the BBC the government "seems paralysed in the wake of real concern about the increase in violence".
But Justice Secretary Jack Straw insisted the government's policies on gun crime were working.
Mr Straw told BBC News 24: "We are concerned that the number of gun-related incidents have gone up, but it has now started to fall as a result of measures introduced by my predecessors over the past three to four years."
But Mr Herbert said: "Frankly, I think it is a feeble response. Amnesties have a place. They had a place in trying to deal with knife crime before and knife crime has doubled in the last couple of years."
The government's proposals follow the fatal shooting of Rhys Jones, 11, on Wednesday.
Mr Straw stressed that gun crime could not be dealt with by the government and police alone, and he urged anyone on Merseyside with information about Rhys's murder to come forward.
"I think that everybody has accepted now this is an issue beyond politics", he said.
A war of statistics has broken out in the debate about Britain's gun and gang culture, which was reignited by Rhys Jones's murder.
The Tories say that, while overall gun crime is down, the number of deaths and injuries from gun attacks in England and Wales has risen from 864 in 1998-99 to 3,821 last year.
"It is clear from the Home Office's own figures that the number of deaths and injuries from gun crime has quadrupled under this government," said Mr Herbert.
Meanwhile, an independent charity has suggested that Home Office figures show the numbers of children killed in recent years are falling.
The Centre for Crime and Justice Studies found 63 children aged from one to 15 were killed in England and Wales in 1995, compared with 31 in 2005/06.
The director of the centre, Richard Garside, said the figures differed from the common perception, but it was too soon to say whether the recent spate of child killings would reverse the downward trend.
He said the most significant rise in killings was among the 16 to 49 age group, up from 429 in 1995 to 513 in 2005/06.
'Question of confidence'
The "drop-off zone" proposals were announced by Home Secretary Jacqui Smith on Saturday.
Liberal Democrat leader Sir Menzies Campbell welcomed the idea but warned it must be coupled with efforts to persuade young people that they do not have to carry a gun.
The Police Superintendents' Association said it supported any initiative that leads to fewer guns on the streets.
But the association's president, Ian Johnston, told BBC Radio 4's World This Weekend there were a number of questions about neutrality and whether people would believe that the police were not involved.
He said people needed to feel confident that they could hand a gun in without "getting a knock on the door".
Not an amnesty
In an interview in Sunday's News of the World, Ms Smith said people who knew where firearms were hidden or were holding them for a relative or friend needed to be able to come forward without revealing their identity and without necessarily contacting the police directly.
"The most suitable place may not be a local police station," she said.
"It may be a voluntary organisation that can work with the police and others where family members can go to and feel confident they can get that gun off the streets or out of their family home.
"This means we can actually take that gun out of circulation and stop it from doing harm."
Angela Lawrence, from Mothers Against Violence, said such a scheme could work through a voluntary organisation "which knows its community and serves its community".
"It would build trust and what we want is guns off our street and we have to be creative to achieve that," she added. "I think it is one solution to a big problem - why not try it?"
A Home Office spokesman said trials would run in areas where gun crime was worst. The government is in talks with the police about exactly where and when these would take place.
About half of all gun crime takes place in the cities of Liverpool, Manchester and London, he said.
The Home Office stressed the scheme would not be an amnesty for illegal weapons, rather an attempt to get them off the streets.
Anyone wishing to inform on people anonymously can already do so via Crimestoppers.