A damning report has highlighted major police failings including failing to track suspects, downgrading emergency calls and not carrying out basic functions.

The police watchdog Her Majesty's Inspectorate of Constabulary (HMIC) also said that the lack of detectives and investigators was turning into a "national crisis".

Its report showed how in many instances, emergency calls were downgraded to allow for a slower response time. In addition, some crimes were "written off" meaning thousands of suspects were left to roam free. Also junior officers were often forced to carry out complex investigations.

This "rationing" was used to manage demand although the report did not specify whether it was due to funding cuts or an issue of management.

Zoe Billingham from HMIC said: "I'm raising a red flag to warn forces of the consequences of what is, to all intents and purposes, an unconscious form of rationing of police services.

"We are leading to a very serious conclusion regarding the potentially perilous state of British policing in this report."

The report highlighted measures some forces had deployed to manage demand - although in each case it was not entirely clear whether they were directly caused by cuts or local management decisions.

While it found that most of the country's 43 police services provided a good service, three forces, Hertfordshire, Humberside and Nottinghamshire, had not been "responding appropriately" to emergency calls.

It also criticised how Hampshire, Sussex and Devon and Cornwall police had carried out phone assessments of domestic abuse victims rather than in person.

However, most of the police forces were rated as "good" or "outstanding", while only one, Bedfordshire police, was rated as inadequate.

Home Affairs select committee chair Yvette Cooper said the report raised "grave concerns", as the shortcomings came in the face of budget cuts, policy changes and rising demand, the Independent reported.

Chief Constable Michael Barton of the National Police Chiefs' Council, said there are now 32,000 fewer officers in five years after budgets had been cut by more than a fifth.

"It's a simple reality that we are required to prioritise more. Difficult decisions are being made between resourcing neighbourhood teams, response units, specialist investigations and digital and cyber-enabled crime. There are no easy answers," the BBC reported.