Thousands of suspects in violent and sexual crimes have been released without conditions since changes to police bail came into effect, it is reported.
More than 3,000 people were released under investigation for offences such as murder and rape by 12 police forces over a three-month period, according to the BBC.
Figures released to the broadcaster under the Freedom of Information Act, covering April to June 2017, found these included 1,692 people arrested for violent crimes, 768 rape suspects and 31 questioned on suspicion of murder.
The Home Office said it had asked forces to review their use of bail.
It comes after a 28-day limit on pre-charge bail came into effect in April last year, as part of a Government shake-up aimed at ending the "injustice" of individuals being kept under a cloud of suspicion for very long periods of time.
The new measures also meant bail could only be used when deemed "necessary and proportionate".
According to the BBC, which sent requests to all 43 police forces in England and Wales but received data from 12, the figures also showed the number of suspects bailed had fallen by two-thirds.
In the three-month time frame, 6,683 suspected violent and sexual offenders were released without further action, 2,430 were charged and 3,149 released under investigation, the broadcaster said.
Suspects who are released "under investigation" are still subject to police inquiries but are not subject to bail conditions.
A spokesman for the Home Office said: "Reforms to pre-charge bail balance carefully the interests of victims and witnesses, those on bail and the police.
"Pre-charge bail, including conditions, continues to be available where it is necessary and proportionate, such as to protect victims and witnesses, while the reforms should also reduce the possible negative impact on individuals on bail, such as mental trauma and financial implications.
"The Minister for Policing and the Fire Service wrote to chief constables in December, asking them to review their forces' use of bail in order to ensure that those who objectively should be on bail are not being released without conditions."