A lawyer for the family of a murdered British girl accused The News of the World tabloid of hacking into her cell phone after she went missing.

The new claims added to a widening scandal surrounding the tabloid newspaper, which is under police investigation and battling lawsuits into its alleged phone-hacking activities.

Lawyer Mark Lewis said that The News of the World hacked into the cell phone voicemail of 13-year-old Milly Dowler when she was first reported missing in 2002.

She was later murdered by a nightclub doorman.

The alleged hacking could have jeopardized the police investigation, Lewis said.

He said Dowler’s parents are pursuing a claim for damages from the Rupert Murdoch-owned tabloid.

The Guardian newspaper has now reported that an investigation it conducted found that The News of the World not only recorded messages left by Dowler’s family and friends, but also deleted the messages in a bid to free up space for more messages.

News International, the publisher of the newspaper, said the allegations were of “great concern” and said it would be conducting its own inquiry.

“This particular case is clearly a development of great concern and we will be conducting our own inquiries as a result. We will obviously cooperate fully with any police request on this should we be asked,” the company said in a statement.

Police refused to comment on the allegations.

The company has admitted wrongdoing and reached cash settlements with several people who claimed their phones were hacked into — including actress Sienna Miller.

A private investigator and a royal editor who worked for News of the World were jailed in 2007 for tapping the phones of royal household staff.