CIA Director Leon Panetta revealed Thursday that senior members of his agency have misled members of Congress repeatedly since 2001 on U.S. interrogation techniques.

It is unclear exactly what Panetta disclosed to lawmakers, but chairman of the House Intelligence Committee Silvestre Reyes claims the CIA outright lied in one case.

The chairman is considering launching an investigation.

Reyes, along with six of the other 13 Democrats on the panel, sent Panetta a letter on June 26 calling for a retraction of a May 15 statement that claimed it is not CIA "policy or practice to mislead Congress."

Earlier this year, House Speaker Nancy Pelosi accused the CIA of lying to Congress about interrogation techniques being used on Al Qaeda detainees.

On Thursday, Pelosi said the House intelligence committee overseas intelligence communications in the House, and its equivalent committee in the Senate.

"I know what you know," she said. "I've seen the letters from the members and obviously they have concerns. I'm sure they will be pursuing this in their regular committee process and that's the way it will go."

The top ranking Republican on the intelligence committee Peter Hoekstra called the news "bizarre."

James Ware, spokesman for Hoekstra, also accused the chairman of trying to deflect Pelosi's claims that the CIA lied to her about water boarding.

Sources: Fox News, ABC News