More than 1,000 people were warned by police last year that they were the subject of a murder plot, The Times has learnt.

Senior officers across the country issued so-called Osman warnings to businessmen, drug dealers and gang members after receiving specific intelligence that they were at serious risk of being killed by individuals with the resources to arrange their death.

Police forces in England and Wales spent millions of pounds gathering information and conducting covert and open operations to prevent the murders.

Osman warnings were issued to 1,028 people, including 177 women, last year. The figures, obtained by The Times under the Freedom of Information Act, do not include the less specific “threat to life” category, when the intelligence does not show who is going to be killed.

A total of 1,713 Osman and “threat to life” warnings were recorded by West Midlands Police, but were not broken down further. Other types of warning can include a threat to a company, premises or someone who has not been named in files.

Of the 43 forces in England and Wales, 28 provided figures of Osman warnings. The remaining forces either did not hold the information, or said that it was too expensive to retrieve under freedom of information rules. Only Merseyside refused to release figures, which it deemed not to be “of benefit to the public interest”.

According to the figures released, Greater Manchester Police issued the most Osman warnings, at 225. Other forces with high numbers include Surrey with 117, Humberside with 90, Bedfordshire with 81 and the Metropolitan Police with 75. Surrey issued 82 Osman warnings to women, the most of any force.

The threats can involve a dramatically growing fallout between individuals, criminal activity, gang-related grudges or the use of contract killers.

One high-profile recipient of an Osman warning in recent years was Johnny “Mad Dog” Adair, the loyalist extremist who moved to the North of England after being released from jail.

Police received specific intelligence that other loyalist paramilitaries were preparing to kill him.

Many of those people warned by police sought alternative accommodation with relatives or moved abroad, while others were taken into the witness protection programme. Some decided to take matters into their own hands, forcing police to take further action to disrupt the actions of both suspected killer and victim.

Often information obtained by police is not sufficient to make an arrest, but requires officers to warn the intended victim.

Detective Superintendent Roger Critchell, from the Metropolitan Police Intelligence Bureau, said that different approaches were required when dealing with threats to kill and threats to life. For threats to kill, an inspector will carry out an immediate risk assessment based on intelligence available. The threat will fall into one of three categories: low, medium or high risk, with medium and high normally given the same priority. A superintendent then assumes control of the plan, supported by an officer from the Metropolitan Police intelligence bureau.

“It does not matter what the potential victim does or is involved in, we have a duty of care to make sure they are safe,” Mr Critchell said. “We will use every asset that we have to make sure the potential victim is safe - we would not rule out surveillance, we may use covert tactics to disrupt or minimise the risk, or overt actions.”

A legal ruling directing that police have a “duty of care” to issue alerts, not only to civilians but also to known criminals, was introduced after a high-profile failure by officers to protect several individuals from Paul Paget-Lewis, a teacher suffering from psychotic tendencies. In 1988 Paget-Lewis shot and wounded a former pupil, Ahmet Osman, to whom he had formed a disturbing attachment, and killed his father, Ali, and two others.

Paget-Lewis’s obsession had been brought to the attention of authorities and police. He was examined on three occasions by a psychiatrist, who decided that he was not mentally ill but should be transferred from the school on medical grounds. He was suspended from teaching duties in June 1987. During this period a number of attacks were made on the Osmans’ property, and were reported to police.

Paget-Lewis, who had changed his name to Paul Ahmet Yildirim Osman, was later interviewed at his own request by education officials. He admitted feeling totally self-destruc-tive, blamed the deputy headmaster, and said he was thinking of doing a “Hungerford”, a reference to the indiscriminate mass killing carried out in the Berkshire town. The police were informed and took some measures to protect the deputy headmaster.When he was arrested, Paget-Lewis said: “Why didn’t you stop me before I did it, I gave you all the warning signs?”

He was later convicted of manslaughter on the ground of diminished responsibility. Ali Osman’s widow, Mulkiye, took the case to the European Court of Human Rights after the Court of Appeal barred her from suing the Metropolitan Police for negligence over the police’s failure to prevent the attack. Judges in Strasbourg ordered the Government to pay the Osmans compensation of £20,000.

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