London (CNN) -- A former editor for the News of the World was released without charge Friday by British police hours after he had been taken into custody, but was told to report back to police in October.
Andy Coulson was arrested earlier Friday in connection with allegations of phone hacking and corruption in a case that promises to be a growing political liability for Prime Minister David Cameron, whom Coulson had served as press secretary.
"I came in today voluntarily as I have been offering to do in the last few months," Coulson told reporters outside Lewisham Police station. "There is an awful lot I would like to say but I can't."
The newspaper's former royal correspondent, Clive Goodman, was also taken into custody Friday. Metropolitan police would not say whether he was released, but implied that was the case. In a statement, police said that a 53-year-old man had been arrested in connection with corruption allegations and was released.
Goodman, 53, had been sentenced to four months in prison in 2007 over the phone hacking.
Another arrest occurred Friday night, when police said officers from the Operation Weeting team had arrested a 63-year-old man at a residence in Surrey on suspicion of corruption. The team is conducting the phone hacking investigation.
The scandal has prompted questions over the British prime minister's judgment in hiring Coulson after he resigned as editor of the News of the World because of the allegations.
Speaking shortly before his former aide's arrest was announced, Cameron went on the defensive at a Downing Street news conference Friday, saying: "The decision to hire him was mine, and mine alone."
He said he gave Coulson a second chance after receiving assurances that he had not been involved in wrongdoing at the newspaper.
Coulson had resigned from the News of the World after its then-royal editor, Goodman, and a private investigator, Glenn Mulcaire, were jailed for intercepting voice-mail messages left for royal aides. Coulson denied knowledge of their activities.
Asked about media reports of a search of the offices of the Daily Star, where Goodman now works, police said there was an ongoing search of business premises in central London, but did not confirm that the Daily Star building was involved.
Meanwhile, prosecutors have asked Strathclyde Police in Scotland to look into allegations of phone hacking and data protection breaches "in light of further emerging developments regarding the News of the World."
Earlier Friday, Labour leader Ed Miliband called on Cameron to admit the "appalling error of judgment" he had made in hiring Coulson and to apologize for bringing him into the heart of government.
Cameron used his address to call for full inquiries into the phone hacking scandal, urging a broad reform of the press.
He said the News of the World turmoil "is not just about journalists on one newspaper, it's not even just about the press -- it's also about the police and about how politics works, and politicians too."
A fresh start is needed, he said, after decades in which politicians from the Labour and Conservative parties grew too close to the news media.
"This is a wake-up call," he said. "It's on my watch that the music has stopped and I'm saying loud and clear that the relationship has to change in the future."
Cameron also referred to Rebekah Brooks, the embattled chief executive of News International and former News of the World editor who is said to be a friend of Cameron, saying that he would have accepted her reported offer to resign. News International is the parent company of New of the World.
The prime minister said the full public inquiry into wrongdoing at the paper should be led by a judge to ensure its impartiality, with "no stone left unturned." But it will not begin until after a police investigation into alleged criminal activity has concluded.
However, he said, a second independent inquiry into "the culture, the practices and the ethics of the British press" should begin as soon as this summer and look into a new system of regulation.
The public has been let down by the police, the politicians who represent them and the news media, Cameron said, and he promised to do everything he can to give people a press that is "clean and trustworthy."
On Thursday, the News of the World's parent company, News International, announced that Sunday's edition of the scandal-hit tabloid will be its last.
The move followed accusations that the News of the World illegally eavesdropped on the phone messages of murder and terrorist victims, politicians and celebrities, and claims it may have bribed police officers. Police said Thursday they had identified almost 4,000 potential targets of hacking.
If Coulson is implicated, the fallout could have damaging consequences for Cameron.
He is close to current and former top officials at News International, former Tony Blair spokesman Alastair Campbell told CNN Thursday.
Miliband said Cameron must "come clean" about any conversations he may have had with Coulson about phone hacking, before and after Coulson was appointed communications chief.
Coulson resigned as editor in January 2007 after Goodman and Mulcaire were jailed. After he moved to his communications role with the Conservative Party, the scandal resurfaced.
Coulson was questioned by police in November and resigned from his Downing Street position last January, despite the Crown Prosecution Service ruling that there was "no admissible evidence" to bring criminal charges.
Miliband said the system of self-regulation through the Press Complaints Commission has failed. He described the press watchdog as a "toothless poodle" in need of reform.
A new body with more independence is needed, he said, to restore the reputation of British journalism.
He also said politicians must take some of the blame for letting the news media gain too much power.
"For too long, the political class have been too concerned about what people in the press would think and too fearful of speaking out" rather than standing up for the rights of the people, he said.
And he urged senior executives at News International, including the chairman, James Murdoch, to take responsibility for the scandal.
"I welcome James Murdoch's admission of serious errors. But closing the News of the World, possibly to reopen as the Sunday Sun, is not the answer. Instead, those who were in charge must take responsibility for what happened."
The scandal has heightened debate over a proposed takeover of broadcaster BSkyB by News Corp., which owns News International. All are part of the media empire of Rupert Murdoch, father of James Murdoch.
Culture Secretary Jeremy Hunt will consider the impact of the News of the World's closure as he reviews its bid for BSkyB, his department said.
Miliband joined other members of parliament in expressing concern over the deal, saying it has "significant implications for media ownership in Britain" at a time when public confidence in News Corp. executives is low.
James Murdoch said Thursday, in announcing the shutdown, that the scandal had "sullied" News of the World and "has no place in our company."
And paying out-of-court settlements to some victims was "wrong and a matter of serious regret," he said.
The paper's roughly 200 employees are now out of jobs, but are free to apply for other positions within News International, the company said. The layoffs have angered union representatives.
On Wednesday, Rupert Murdoch called allegations against his flagship Sunday paper "deplorable and unacceptable."
News of the World was the first British national newspaper Rupert Murdoch bought, in 1969, as he began to propel himself from Australian newspaper proprietor to international media magnate.
In addition to owning News of the World, News International owns the Sun, the Times and the Sunday Times in Britain.
Murdoch's News Corp. also encompasses Fox News, the Wall Street Journal, the New York Post and Harper Collins publishers.
CNN's Laura Smith-Spark, Richard Allen Greene and David Wilkinson contributed to this report.