WASHINGTON — CIA Director Leon Panetta has terminated a "very serious" covert program the spy agency kept secret from Congress for eight years, Rep. Jan Schakowsky, a House Intelligence subcommittee chairwoman, said Friday.

Schakowsky is pressing for an immediate committee investigation of the classified program, which has not been described publicly. Rep. Silvestre Reyes, D-Texas, the chairman of the House Intelligence Committee, has said he is considering an investigation.

"The program is a very, very serious program and certainly deserved a serious debate at the time and through the years," Schakowsky told The Associated Press in an interview. "But now it's over."

Democrats revealed late Tuesday that CIA Director Leon Panetta had informed members of the House Intelligence Committee on June 24 that the spy agency had been withholding important information about a secret intelligence program begun after the Sept. 11 terrorist attacks.

Schakowsky described Panetta as "stunned" that he had not been informed of the program until nearly five months into his tenure as director.

Panetta had learned of the program only the day before informing the lawmakers, according to a U.S. intelligence official. The official spoke on condition of anonymity Friday because he was not authorized to discuss the program publicly.

Panetta has launched an internal probe at the CIA to determine why Congress was not told about the program. Exactly what the classified program entailed is still unclear.

The intelligence official said the program was "on-again/off-again" and that it was never fully operational, but he would not provide details.

Schakowsky, D-Ill., said Friday that the CIA and Bush administration consciously decided not to tell Congress.

"It's not as if this was an oversight and over the years it just got buried. There was a decision under several directors of the CIA and administration not to tell the Congress," she said.

Schakowsky, who chairs the Intelligence subcommittee on oversight and investigations, said in a Thursday letter to Reyes that the CIA's lying was systematic and inexcusable. The letter was obtained by The Associated Press on Friday.

She said Reyes indicated to her the committee would conduct a probe into whether the CIA violated the National Security Act, which requires, with rare exceptions, that Congress be informed of covert activities. She told AP she hopes to conduct at least part of the investigation for the committee.

She said this is the fourth time that she knows of that the CIA has misled Congress or not informed it in a timely manner since she began serving on the Intelligence Committee two and half years ago.