Former News International chief executive Rebekah Brooks has been questioned by police about payments to Ministry of Defence officials.
She is understood to have been asked about evidence handed over by News Corporation's Management and Standards Committee.
The 41-year-old was answering bail in Milton Keynes relating to her first arrest by Operation Weeting last summer. Both Scotland Yard and Mrs Brooks's spokesman declined to comment.
Mrs Brooks, a former editor of The Sun, was first arrested by detectives in July on suspicion of phone hacking and corruption, days after she quit News International.
She answered bail today after being rearrested last week with her racehorse trainer husband Charlie on suspicion of conspiracy to pervert the course of justice.
Police searched several addresses in Oxfordshire, London, Hampshire and Hertfordshire after the couple were held along with four other suspects.
Her lawyer, Stephen Parkinson, recently said evidence given by Metropolitan Police Deputy Assistant Commissioner Sue Akers at the Leveson Inquiry had brought "much prejudicial material" into the public domain.
Mrs Brooks' relations with top police officers and politicians have been called into question in recent weeks after it emerged that she "fostered" a police horse when it retired from active service in 2008.
She paid food and vet bills until the animal, called Raisa, was rehoused with a police officer in 2010, months before fresh investigations began into illegal activities at the News of the World.
A total of 22 people have been arrested under Weeting, which has been running since January last year, Scotland Yard said.