Former Union minister P Chidambaram was arrested by the Central Bureau of Investigation this evening after high drama outside his South Delhi home, complete with slogan-shouting supporters, police and unprecedented visuals of CBI investigators scaling walls and roof to gain access inside. He has been taken to the CBI office for questioning. The race started earlier this evening as the senior leader -- sought by investigative agencies for nearly 24 hours in connection with a corruption case -- appeared at the Congress headquarters.