The former communications chief to British Prime Minister David Cameron, along with a former editor, were arrested Friday as part of an investigation into alleged telephone hacking involving the News of the World tabloid.

Former Cameron spokesman Andy Coulson – who once worked as an editor at the paper – was detained for suspected corruption and conspiring to intercept communications. The newspaper's former royal editor, Clive Goodman, was taken into custody as well.

Both men have now been released on bail, but Coulson will have to report to police in October. Coulson left the paper in 2007, the year Goodman and a private investigator spent time in jail over allegations they hacked into the phones of royal aides. The Associated Press also reports police have arrested a third person in the scandal.

Police also searched the newsroom of a second tabloid, the Daily Star, where Goodman had been working since his release.

Prime Minister Cameron told reporters Friday that he gave Coulson a “second chance” to serve as media adviser after the former News of the World chief provided assurances of not having any knowledge of the incidents. But Mr. Cameron admitted his appointment of Coulson did not work out.

The prime minister was quoted as saying he takes “full responsibility” for his decision to appoint Coulson, who resigned in January as it became clear the alleged hacking had been widespread.

British media revealed this week that the investigation of the tabloid has expanded to include allegations it eavesdropped on voicemails sent to the phones of murdered schoolgirls, victims of terrorism and slain soldiers. Other accusations include paying bribes to police for information on stories.

The revelations triggered public outrage and forced the paper's parent company, News Corporations, to announce that the best-selling, 168-year-old tabloid will shut down after publishing its next Sunday edition.

Mr. Cameron promised Friday that a judge will lead a full public inquiry into the scandal after police conclude the investigation. He also pledged to appoint an independent panel to draft new regulations for British news organizations, whom he accused of failing to properly regulate their own conduct.

The prime minister said leaders of British political parties had long turned a “blind eye” to bad media practices in order to win the endorsements of newspapers.

Mr. Cameron said he heard reports that the chief executive of News Corporation's British unit, News International, has offered to resign over the scandal. Chief executive Rebekah Brooks previously managed the News of the World when many of the alleged phone hacking incidents took place, although she denies knowing anything about them at the time.

Mr. Cameron said he would accept Brooks' resignation if it were up to him.