Sullivan, who resigned shortly after the $4bn (£2.5bn) WorldCom accounting fraud was exposed, was taken into custody along with former controller David Myers.
It is not yet known what the two have been charged with. According to reports Sullivan and Myers were led away in handcuffs, in exactly the same manner as Adelphia founder John Rigas was arrested.
The arrests follow investigations by federal authorities into the two executives alleged role in the $4bn (£2.5bn) accounting scandal WorldCom admitted to in June.
The company said it inflated profits by claiming operating expenses as capital spending.
Mark McMullen joins the private client services team from Smith & Williamson
Merger between Clear & Lane Chartered Accountants and Magma Chartered Accountants was finalised on 3 February
BDO has taken its new partner intake to 23 during the first half of its financial year, including the appointment of five partners in five weeks
The firm reports 7.6% global fee income growth for the year ending 31 December 2016