A four-member team on Saturday interrogated former president Pervez Musharraf for two hours and 40 minutes.
The team, headed by FIA additional Secretary FIA Khalid Qureshi, conducted the investigation at his Islamabad residence that has been declared a sub-jail.
According to sources, the team handed over a questionnaire to the former president.
He was asked as to who issued the orders to wash the crime scene on December 27, 2007 after the murder of Benazir Bhutto (BB), and on what basis he had warned Benazir Bhutto about the possible terror attack on her return.
To this, Musharraf said that he was then president and it was not his responsibility to provide security to BB, adding that this question should be asked to then PM and authorities concerned.
The team also asked Musharraf about his email to US journalist Mark Seagal.
Musharraf, who is on a four-day remand, will be presented before a court on April 30.