London (CNN) -- A powerful British media group is fighting new accusations that it illegally got information on members of the royal family and top politicians, after a lawmaker accused it of hacking.

Police have information that "strongly suggests" that a private investigator targeted royals, lawmakers and high-level terrorist informers on behalf of Rupert Murdoch's News International, Labour lawmaker Tom Watson said in Parliament Wednesday.

British media said the targets included former Prime Minister Tony Blair and Kate Middleton when she was dating Prince William, the second in line to the throne. They married in April.

Buckingham Palace and Prince William's office at Clarence House both declined to comment.

But London's Metropolitan Police told CNN Thursday it "has received a number of allegations regarding breach of privacy.... These allegations are currently being considered."

News International rejected the accusation.

"With regards to Tom Watson's specific allegations, we believe these are wholly inaccurate," the company told CNN Thursday, adding that it was cooperating with ongoing police investigations into phone hacking and had not been asked about the work of the private investigator Watson named in Parliament.

But it said it was "well documented" that the investigator "worked for a whole variety of newspaper groups."

Murdoch's media group, which owns the Sunday tabloid News of the World, has already apologized to a number of celebrities and offered them compensation after admitting it had their phones hacked.

Actress Sienna Miller was among the victims, a British court ruling in June confirmed.

A News of the World royal correspondent and a private investigator were sent to prison in 2007 for hacking into the voice mails of members of the royal staff.

But Watson named a different investigator Wednesday, undercutting the long-standing News International claim that the practice of phone hacking was not widespread.

The Metropolitan Police are conducting an investigation called Operating Weeting into the accusations of hacking by British media.

They said Thursday the allegations they have received this year are "outside the remit of Operation Weeting."

But Prime Minister David Cameron said Thursday that a "police inquiry does not need terms of reference" and that police are "free to investigate the evidence and take that wherever it leads them."

Murdoch's media empire encompasses the Wall Street Journal, the New York Post, Fox News and Harper Collins publishers, as well as the Times and the Sun newspapers in London.

CNN's Richard Allen Greene, Carol Jordan and Bharati Naik contributed to this report.