NEW YORK (CNN/Money) - The exodus of the founding family of Adelphia Communications Corp. continued Thursday as chief financial officer Timothy Rigas left the company a day after his father stepped down as CEO.

Adelphia (ADLAE: Research, Estimates) said responsibility for the company's books, which are under investigation by the Securities and Exchange Commission, will be taken over by a special committee of the board of directors and outside financial advisers.

The nation's No. 6 cable TV operator has been under fire for failing to disclose it had guaranteed at least $1.6 billion in loans to Rigas family members. Adelphia's stock tumbled this spring after it revealed off-the-books debt and confirmed that the SEC was investigating its accounting practices.

The company said the special committee, which will consist of three independent directors, also will "have broad powers to conduct a full and thorough investigation into a number of issues, including ones regarding transactions between the company and certain entities controlled by the Rigas family."

"Our top priority is to restore the confidence of our lenders, shareholders and the marketplace as a whole," interim CEO Erland E. Kailbourne said. "The only way to do that is to have a complete, unflinching review of all the questions that have been raised, and to make a full and candid disclosure of each and every problem the company finds to exist."

The SEC is probing Adelphia's accounting for $2.3 billion in off-the-books debt. Adelphia disclosed the investigation April 3. The debt includes loans, possibly as much as $500 million, made to members of the Rigas family, who apparently secured the loans with Adelphia's assets.

Earlier this month Adelphia said it expected to restate its financial results for three years to reflect the off-the-books debt, worth about $1.6 billion on May 2, and that it was reviewing its accounting methods.

Timothy Rigas, like his father, will retain his seat on the board of directors.

Shares of Adelphia have been halted since pre-market trading on Wednesday.