Violent criminals are being freed on bail to commit murder amid the prison overcrowding crisis, the country's top police officer warned.

Met Commissioner Sir Mark Rowley said he was 'flabbergasted' at the growing number of suspects charged with gun and knife crimes who are being let back on to the streets.

Sir Mark said he expected to see a rise in violent crime, with some offenders still being freed on bail on their fourth offence of being caught with a weapon.

In explosive testimony to the London Policing Board, the Scotland Yard chief revealed that more than 30 people charged with serious firearms offences in London alone were currently on bail.

And the Mail can reveal that there are now a staggering 3,000 electronic tag breaches by bailed suspects every week across England and Wales.

In nine out of ten cases, the courts re-release them on bail, which will embolden serial offenders, police chiefs fear.

Victims' advocates said the creaking criminal justice system was now creating serious implications for public safety.

It comes as thousands of criminals are set to be let out early under Labour's controversial Sentencing Act aimed at tackling overcrowding.

Sir Mark said: 'This isn't a theoretical risk. We are seeing stabbings and in one or two cases homicides committed by people who would previously have been on remand in custody. This is really troubling.'

In the last six months alone, the number of bailed suspects breaching their electronic tag conditions has rocketed by nearly 50 per cent in London alone, from 2,977 in January to 4,408 in July.

Breaches can include going on the run, contacting a victim, flouting a curfew, attempting to remove a tag or going to a prohibited area.

The Met Commissioner added: 'In more than 95 per cent of those cases we arrest them, put them before the courts and nothing changes, so that looks like nugatory [futile] effort.'

In some instances, those released on bail are going on to carry out murders. 

Sir Mark warned falls in knife crime were 'starting to turn' as a result of 'compromised' offender control, adding: 'I'm really worried about that.

'We are seeing rapidly reducing imprisonment for people sentenced for knife crime offences, even repeat knife carriers.

'At the start of the process far fewer are being remanded in custody, so routinely now we are seeing people charged again, and again, and again with carrying knives and they are being bailed again, and again, and again, and that really concerns me.' 

At the weekend, a repeat knife offender on bail was caught trying to smuggle an 18-inch sword into the Notting Hill Carnival in his fourth blade offence that year.

Sir Mark said: 'He is on bail and has two knife referral orders and tries to take something that looks like a small sword into Notting Hill Carnival and he is bailed again. 

'That is deeply concerning to me – the message that sends and that fundamentally undermines offender control. We are now seeing it on firearms offences as well and I'm flabbergasted by this.

'There are 34 cases of people being charged with firearms offences in London pending trial who are on bail, in nine of those cases they have fired shots in confrontations and they are on bail.'

Police chiefs fear Labour's soft justice reforms will make matters worse as short sentences are ditched, meaning fewer offenders will be jailed, and police will have to monitor thousands of criminals released early.

Jason Hogg, Chief Constable of Thames Valley Police, agreed that soft-touch bail conditions were a symptom of a 'criminal justice system in crisis'. 

He said: 'Already the whole Sentencing Act hasn't properly kicked in and I'm receiving reports it's more difficult to remand people to custody. 

'We have about 4,000 breaches of court bail each week. And in over 90 per cent of those, the conditions aren't changed.'

The warning comes after a series of cases where suspects freed on bail have gone on to commit murders.

Victims' Commissioner Claire Waxman said: 'What started as a prison capacity crisis has evolved into a whole-system challenge for criminal justice, with implications for public safety, victim confidence and the effective operation of prisons, probation, policing, courts and victim services.'

A government spokesman said that since Labour took office 'knife crime has fallen by 11 per cent and knife homicides by 26 per cent'. 

The spokesman added: 'Bail decisions are a matter for the independent judiciary.'

On Thursday, Donald Trump repeated claims that parts of London were no-go areas as a result of immigration. 

The President also used the GB News interview to renew criticism of London Mayor, Lord Khan of Tooting.

Mr Trump said: 'London's a much different place. You have a terrible mayor. He's a nasty guy, nasty person.

'You have areas in Paris and London where the police don't want to go in them, there's no law and order. They're afraid to go in them.'

But a source close to Lord Khan said: 'Sadiq is still living rent free in Trump's head. The guy is obsessed with him.'

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