Ms. Brooks is the highest-ranking News International official to be arrested. Andy Coulson, a former News of the World editor who went on to become the chief spokesman for the prime minister, was also arrested last summer as part of Operation Weeting. Other suspects include some of the most prominent reporters and editors at The News of the World and The Sun, Britain’s most popular daily newspaper.

Ms. Brooks and Mr. Coulson have maintained that they knew nothing about phone hacking or other illegal activities. David Wilson, a spokesman for the Brookses, did not return a call seeking comment.

According to a statement from the Metropolitan Police, the ages of the suspects arrested Tuesday ranged from 38 to 49, and all but one were men. Five were arrested at home: two in Oxfordshire (these are believed to be the Brookses), one in Hampshire, one in West London, one in Hertfordshire and one in East London. The sixth suspect, the police said, was arrested at a business address in East London.

It is unclear what Mr. Brooks, a horse trainer with strong Conservative ties who appears to have been drawn into the investigation by virtue of his marriage, is suspected of having done. But The Guardian reported in July that he was involved in a peculiar episode featuring a laptop left in a bag in a garbage can in an underground parking garage near the London apartment he shares with his wife.

According to The Guardian, the bag, which also held some papers, was unearthed by security guards, who called the police. Mr. Brooks then tried to reclaim the items but could not prove they were his.

A spokesman for Mr. Brooks told the newspaper that he had “left the bag with a friend who was returning it, but dropped it in the wrong part of the garage.” When asked how the bag had ended up in a garbage can, the spokesman replied, “The suggestion is that a cleaner thought it was rubbish and put it in the bin,” and added that it had been “nothing to do with Rebekah,” the newspaper said.