Madoff whistleblower gives SEC new tips

Harry Markopolos, the fraud investigator who was repeatedly rebuffed by the Securities and Exchange Commission in his efforts to blow the whistle on Bernard Madoff, Thursday presented SEC Inspector General David Kotz with evidence of two new potential cases of investment fraud.

"Pursuant to an agreement with him I've handed those tips to the office of the [SEC] Chairman Mary Shapiro," Kotz told CNN. Kotz said he could not elaborate on the tips from Markopolos.

Kotz and members of his staff met with Markopolos and two of his attorneys for seven hours Thursday, as part of the inspector general's investigation into the SEC's failure to uncover Madoff's alleged scam.

"He's a key witness in our investigation," said Kotz. "It was a very productive meeting. We received a tremendous amount of good information."

Kotz said he is still months away from issuing a report on the SEC's performance in the Madoff matter. Testifying before the House Subcommittee on Capital Markets Wednesday, Markopolos slammed the SEC's failure to heed his warnings that Madoff was a fraud.

"I gift-wrapped and delivered the largest Ponzi scheme in history to them and somehow they couldn't be bothered to conduct a thorough and proper investigation," said Markopolos.

Madoff remains under 24-hour house arrest at his luxury apartment on Manhattan's Upper East Side. A former Chairman of the Nasdaq Stock Market, Madoff told FBI agents he had operated a scheme that may have cost investors $50 billion, according to a criminal complaint. He faces one count of securities fraud.