Channel 4 News has learned that Scotland Yard is now formally investigating allegations that a senior murder detective was put under surveillance by the News of the World in 2002.

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At the time Dave Cook was leading a highly sensitive investigation into the murder of Daniel Morgan, a private investigator who was found in the car park of a south london pub 24 years ago with an axe buried in his head.

Earlier this year Channel 4 News revealed Cook's claims that journalists from the News of the World had been tailing him and putting his house and family under surveillance.

It has been alleged that suspects in the murder investigation were private investigators who had had close links to the News of the World.

Several months after the alleged surveillance, Cook raised the issue directly at a meeting at Scotland Yard with the then editor of the News of the World Rebekah Brooks, but Brooks has not yet been able to give an account, in public, of that meeting.

The Metropolitan Police Commissioner at the time, Sir (now Lord) John Stevens, was aware of the meeting, but no formal action by the police appears to have ensued.

Operation Tuleta

Now the Metropolitan Police, nine years on, is investigating the allegations.

In a statement to Channel 4 News they said:

"We can confirm that after MPS contact with solicitors representing the family of Daniel Morgan, officers from Operation Tuleta will examine the circumstances of a meeting that took place at New Scotland Yard in 2002.

"It is understood the meeting was in relation to concerns that a police officer working on the murder investigation was subject to surveillance."