Pakistan's former President Asif Ali Zardari was arrested by officials from the National Accountability Bureau in Islamabad.
He was arrested after an appeal for an extension of the pre-arrest bail was rejected by the Islamabad High Court on Monday.
Zardari appeared in court alongside his sister Faryal Talpur, a member of his Pakistan People's Party whose appeal was also rejected.
Both are facing charges in connection with the fake bank accounts scandal.