On Friday, the Chairman of Senate Banking Committee demanded the task force to investigate thoroughly the violations of the law at Lehman Brothers and other firms. Later, Senator Christopher Dodd wrote to Attorney General Eric Holder saying that, he was truly concerned with the accounting manipulation of Lehman Brothers.

He also demanded a special task force to look into the matter and prosecute those who are involved in the violation of the law.

Mr. Lee, who headed the firm's global balance sheet, also said that Lehman had 10 billion Dollars of unsubstantiated balances.

"I believe the manner in which the Firm is reporting [certain] assets is potentially misleading to the public and various governmental agencies", Mr. Lee wrote.

Later, when Mr. Einhorn said that, by writing up the value of KSK Energy, the firm had booked a $400 million to $600 million gain in the first quarter, Lehman replied that the investors had put in more funds than Lehman's own investment.

Mr. Lee, who was terminated in May, brought up his concerns about Repo 105 when he was asked to come back to Lehman where he was interviewed by Ernst & Young auditors about his complaints.

Later, Mr. Lee and Lehman ultimately negotiated a severance agreement.