London (CNN) -- Rebekah Brooks, the former editor of the British tabloid News of the World and a confidante of its owner, Rupert Murdoch, was arrested Tuesday in connection with a phone-hacking investigation, police said.
London's Metropolitan Police refused to name her, but said the woman arrested Tuesday had previously been arrested July 17, the date Brooks was arrested. She was the only one arrested in connection with phone hacking that day.
News International's head of security, Mark Hanna, was also arrested, according to an internal message sent to staff by the company's chief executive, Tom Mockridge, the Times newspaper reported. The Times is one of News International's titles.
Dozens of current and former employees of News International, the News Corp. subsidiary that publishes Murdoch's British newspapers, have been arrested on suspicion of bribing police or illegally intercepting voice mail or e-mail. No one has been charged.
Accusations of widespread phone hacking on behalf of News of the World prompted its publisher to fold the publication last July.
Brooks had previously been arrested in connection with phone hacking and police bribery, and was released on bail after a day of questioning.
She was among six people detained Tuesday on suspicion of conspiracy to pervert the course of justice, police said.
She was also presumably one of the five people reported by Metropolitan Police as having been bailed out on Tuesday. She is "to return pending further inquiries to an Oxfordshire police station on a date in April," police said in a statement. Again, the police did not identify her by name, but did say a 43-year-old woman had been granted bail. Brooks is 43.
The sixth person, identified only as a 38-year-old man, remained in custody at a central London police station, police said.
The widening scandal has spawned three police investigations, two parliamentary committee investigations and an independent inquiry.
Brooks' husband, racehorse trainer Charlie Brooks, was also arrested Tuesday, according to reports in Murdoch outlets, including the Wall Street Journal and Sky News. Charlie Brooks did not return a voice mail message from CNN on Tuesday.
He had been expected to attend the opening day of Britain's Cheltenham horse racing festival Tuesday but was not seen there.
Rebekah Brooks, a former editor of the News of the World and the daily tabloid The Sun, served as chief executive of News International until she resigned days before her arrest in July.
Police investigating phone hacking say that about 5,800 people, including celebrities, crime victims, politicians and members of the British royal family, may have been targets of the practice by journalists.
The hacking involves illegally eavesdropping on voice mail by entering a personal identification number to access messages remotely.
CNN's Alysen Miller, Laura Smith-Spark and Antonia Mortensen contributed to this report.