An investigation conducted by The Independent brought to light claims that senior detectives at Surrey Police had meetings with journalists from the now defunct newspaper.
Mark Rowley said in a letter to the Commons culture committee that the paper had made a call to them in April 2002. The call reportedly confirmed that they had accessed the then-missing schoolgirl's voicemail account. Rowley said that the force's main priority at the time was to find Dowler.
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Rowley said: "From that call it was apparent that person(s) working for, or on behalf of, the NoW had accessed Milly Dowler's voicemail.
"At that time, the focus and priority of the investigation was to find Milly, who had then been missing for over three weeks and significant resources were deployed to achieve this objective.
"I can confirm that Surrey Police did not launch a criminal investigation into how the NoW came by the information it provided Operation Ruby with in April 2002 and that Surrey Police neither arrested nor charged anyone in relation to accessing Milly Dowler's voicemail.
"The inquiry team is currently looking into why this was the case."
Committee chairman Keith Vaz said: "Had Surrey Police acted in 2002, it may have prevented the culture of hacking becoming endemic at News of the World.
"The committee will be investigating further the reasons why Surrey Police did not follow up on this evidence, and why Sussex Police did not flag it up in their review of Operation Ruby."
The Independent Police Complaints Commission (IPCC) is currently looking into claims that a police officer working on the Dowler case passed on information to the News of the World.
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