The number of people warned by police that they are at risk of being murdered has soared amid growing fears that gang violence is spiralling out of control and spreading from the capital, figures obtained by The Telegraph reveal.

Forces across England and Wales issued more than 776 so-called “Osman warnings”, or “threat to life” notices, last year. That figure represents a 14 per cent increase compared to 2016 when at least 679 warnings were made, a Freedom of Information request has shown. And, because only 31 of the 43 forces in England and Wales responded to the request the real number of threat to life warnings police made are likely to be far higher. Of those, only 20 had the information available.

Osman warnings are issued if police have intelligence of a real and immediate threat to the life of an individual. In such cases officers may not have enough evidence to make an arrest and so warn the potential victim through a notice or letter that their life is endanger.

The figures offer an insight into how violent crime in the country is escalating at an alarming rate. The extent of that increase is illustrated starkly by figures from the capital’s Metropolitan Police Service, Britain’s biggest force.