Police are failing to solve half of crimes, including nearly three quarters of cases of theft, criminal damage and arson, figures suggest.
Data from 28 police forces in England and Wales, excluding the Metropolitan Police, showed that in April and May this year 52% of crimes were classed as "investigation complete, no suspect identified", meaning that the case is closed unless new evidence comes to light.
This happened in 73% of criminal damage and arson cases, 72% of theft and 56% of robbery, according to figures released by the Home Office, which stressed that the investigations could be reopened later.
Adam Pemberton, assistant chief executive of Victim Support, said: "It is alarming that so many serious crimes remain unsolved. Victims want to know that the police are doing all they can to investigate the crime committed against them.
"Investigating a crime is a matter for police, who also have a duty to keep victims informed and explain decisions made about an investigation. This obligation is set out in the Government's Victims Code."
Today the Office for National Statistics also revealed that crime has fallen to its lowest level since 1981, according to a national survey, but that police figures had remained level for the first time in a decade.
The latest data from the Crime Survey for England and Wales estimated that there were 7.3 million crimes in 2013/14, down 14% on the previous year and the lowest since 1981.
But police figures showed no change compared to the previous year, with 3.7 million offences recorded in the 12 months to March. Before this, data from the forces had shown year-on-year reductions since 2002/03.
This follows changes made after concerns were raised about the poor quality of the way police record crimes, and the figures being stripped of an official gold standard.
The latest data showed that sex crimes were up by 20%, with rape rising by 27%, hitting its highest level since 2002/03.
There was also a rise of 26% in sex crimes against children compared with last year, with 13,610 sexual offences involving a child under the age of 13 in the year to March 2014, the highest level since 2002/2003.
Jon Brown, NSPCC lead for tackling sexual abuse, said: "While the recent focus has, quite rightly, been on historic sexual abuse, these shocking figures show that many young children continue to be at great risk right now. It's horrifying that every day around 30 children under 13 are being sexually assaulted and starkly illustrates what a huge job we have to keep children safe."
Yesterday the National Crime Agency revealed details of a major crackdown on several hundred suspected paedophiles, including doctors, teachers and former police officers accused of accessing depraved images of children online.
NCA deputy director-general Phil Gormley warned that the scale of the issue is so vast that law enforcement cannot be expected to tackle it alone.
The agency has previously estimated that 50,000 Britons are involved in sharing images of child abuse online.
Mr Brown added: "Wednesday's police raids revealed the vast scale of the child abuse images problem which is an abhorrent crime that cannot be solved by law enforcement agencies alone.
"We need the continued help of industry to identify those producing these sordid pictures and block their distribution, as well as public education to change the warped and distorted attitudes of some individuals.
"And of course there must be more services to provide therapeutic treatment for the victims."
Figures from the survey also showed that there were 1.3 million violent incidents, a drop of 20% on the previous year. This is the equivalent of two in 100 adults being victims in 2013/14, compared to five in 100 in 1995.
However, according to police figures, violence rose 6%, by around 33,000 offences, although the number of recorded homicides was 537 - down by 21 from the previous year and its lowest since 1978.
Deaths by dangerous driving rose sharply to 282, up from 174 the previous year.
Mark Bangs, from the Office for National Statistics, said: "Part of the rise in sexual offences is related to the effect of the Operation Yewtree investigation which has brought to light a large number of historic sexual offences.
"The increase is also likely to reflect a broader Yewtree effect whereby more victims are coming forward to report sexual offences to the police."
When figures from around half the forces in England and Wales were analysed, it was found that most of the rise had come from sex offences alleged to have occurred in the previous year, 60%, while 40% were said to have happened more than a year before.
Among all the 43 forces, 36 had seen a rise in shoplifting, including 18% in Merseyside and 17% in Humberside.
Fraud was also up by 17% according to police figures, and analysis showed that 5.1% of bank or credit card users were victims of card fraud, up from 4.6% the previous year.