LONDON - A private investigator working for Rupert Murdoch's News of the World tabloid did not delete voice mails from the phone of a missing girl, a police lawyer said Monday - casting new light on the event that sparked Britain's phone-hacking scandal.

The claim that the tabloid not only listened to but interfered with messages left for 13-year-old Milly Dowler in 2002 triggered a furor this summer that shook Murdoch's global media empire and rattled Britain's police, media, and government.

The scandal exploded after the Guardian newspaper reported in July that the News of the World had eavesdropped on the girl's voice mails after she disappeared and may have hampered the police search for her by deleting messages.

Milly's parents have described feeling elated when they were able to reach her previously full mailbox several days after she disappeared, because it made them think their daughter was alive. In fact, she had been murdered.

Neil Garnham, a lawyer representing London's police force, told Britain's media ethics inquiry that it had been widely reported that someone from the News of the World - most likely private investigator Glenn Mulcaire, who was later jailed for hacking the phones of royal staff - "had deleted voice mail messages to make way for further recordings."

But he said the police had never told the Dowler family that messages had been deleted. Garnham said Mulcaire had not been assigned to the Dowler story until after the messages disappeared, and police had found no evidence pointing to any other employee of the newspaper.

"The most likely suggestion is that existing messages automatically dropped off after 72 hours," Garnham said.

Prime Minister David Cameron set up the inquiry after it emerged that the News of the World had for years illegally eavesdropped on the voice mail messages of celebrities, public figures, and crime victims. Murdoch shut down the newspaper in July.

The Dowler family's attorney, Mark Lewis, said in a statement that the main claims against the News of the World remained, even though it was unclear who had deleted Milly's messages.