Her husband, Charlie, a longtime friend of Prime Minister David Cameron, was also detained, the source told the Times.
Metropolitan Police said six suspects were arrested early Tuesday by detectives investigating telephone hacking by the media, police said.
The suspects, who were not identified by police, were arrested in London, Oxfordshire, Hampshire and Hertfordshire on suspicion of conspiracy to pervert the course of justice. Several of the homes were being searched, The Guardian reported.
Unlike some of the past arrests in the investigation, Tuesday's arrests were not linked to information given to police by News Corp.'s management and standards committee, The Guardian said.
Brooks, 43, worked as the editor of the former News of the World and the editor of The Sun tabloid before being named chief executive of Rupert Murdoch's News International, the Times said. She was also arrested last year on suspicion of phone hacking and illegally paying the police.
Brooks has said she was not aware of phone hacking and illegal payments that have rocked Britain's newspaper industry. She is the highest-ranking News International official to be arrested in the investigation, the Times said.