LONDON, England (CNN) -- British lawmakers demanded answers Thursday after a newspaper reported that a UK tabloid illegally hacked the phones of thousands of public figures including Gwyneth Paltrow, George Michael and Elle MacPherson.
Britain's News of the World tabloid is at the center of the phone-hacking allegations.
Prosecutors said they would look again at claims of alleged phone hacking by the News of the World. However police said they would not conduct a new investigation into the claims by the Guardian newspaper. Metropolitan Police Assistant Commissioner John Yates said officers had seen no additional evidence since its last investigation.
Earlier Thursday the Guardian reported the cell phones of "several thousand public figures" were hacked into by reporters and staff of the News of the World tabloid during one month in 2006.
The public figures named by the Guardian as victims of the phone hackings include lawmaker John Prescott, who was then the deputy prime minister; Tessa Jowell, who was the secretary of state for culture, responsible for the media; and London Mayor Boris Johnson, who at the time was the Conservative Party spokesman on higher education.
The Guardian said actress Gwyneth Paltrow, model Elle MacPherson, actor Jude Law, singer George Michael, celebrity chef Nigella Lawson, celebrity PR agent Max Clifford, and actors union Equity were also victims of the hacking.
"The allegations -- the enormity of it -- is just unbelievable," Prescott told the BBC on Thursday morning.
"I think it is outrageous," former Home Secretary Charles Clarke, who was not named among the alleged victims, told the BBC. "I think we do need action immediately."
Thursday's revelations in the Guardian come from a case last year in which Gordon Taylor, the head of the Professional Footballers' Association, was suing the News of the World for illegally intercepting messages on his cell phone.
The tabloid paid Taylor more than £400,000 ($800,000 at the time) to settle the case, the Guardian said. The case file was sealed, but the newspaper said it obtained the suppressed evidence.
That evidence, the Guardian said, shows that journalists working for the News of the World paid private investigators to illegally hack the cell phones of several thousand public figures. The staff then paid for the information the investigators obtained, the Guardian said.
News International, the parent company of the News of the World defended its journalists and said it would not "shirk from vigorously defending our right and proper role to expose wrongdoing."
In a statement News International, the UK subsidiary of News Corporation, said it was prevented by "confidentiality obligations from discussing certain allegations made in the Guardian newspaper today."
But the statement stressed its staff have been told they must operate within the law and the industry's code of conduct.
Police and prosecutors also came under scrutiny in the Guardian's report. It said the Metropolitan Police were aware of the hackings and raided the offices of some of the private investigators but did not inform those whose phones allegedly were targeted. The paper also said prosecutors decided not to take any legal action over the claims.
Prescott demanded to know why -- if those allegations are true -- he wasn't told that his phone had been allegedly been hacked.
"I am writing to the chief of police to ask him and the Met authorities, did you know that many of our phones were being tapped? Did you tell the public prosecutor? Did the prosecutor then say 'no further action'?" Prescott told the BBC. "I can't believe that such legal authorities -- on such serious charges, if these allegations are right -- did nothing, and I want to know from them."
A spokeswoman for Jude Law said the actor was not commenting on the Guardian's report. Other celebrities contacted by CNN had no immediate comment.
A spokesman for Equity said the union was writing to the commissioner of the Metropolitan Police to ask for evidence accompanying the claims. The Guardian reported that Equity was targeted as a way to get actors' addresses.
"We have no evidence to support the claims in today's Guardian story that Equity was conned into giving out information and we have received no complaints from any of our members that the details we hold on their behalf have been improperly accessed," Equity's letter states. "We do, however, take the claims very seriously. We will be investigating the alleged breach in our security."