WASHINGTON (CNN) -- The Justice Department and the CIA will jointly investigate the destruction of videotapes of CIA interrogations of two al Qaeda suspects, a top official said.
CIA Director Michael Hayden said his agency will cooperate fully with the investigation.
The Justice Department's assistant attorney general for national security, Kenneth L. Wainstein, announced the investigation Saturday in a letter to the CIA's top lawyer, John Rizzo.
The probe will determine "whether further investigation is warranted," Wainstein said.
CIA Director Mike Hayden said his agency will cooperate fully.
"I welcome it as an opportunity to address questions that have arisen over the destruction back in 2005 of videotapes," he said.
President Bush and Vice President Cheney learned about the videotapes Thursday, when Hayden briefed them about the tapes and their subsequent destruction, administration officials said Friday. Watch the explainer on the CIA tapes controversy »
The tapes -- showing newly approved "alternative" interrogation techniques -- were recorded in 2002, Hayden said Thursday in a letter to CIA employees.
Osama bin Laden lieutenant Abu Zubayda was one of two al Qaeda suspects whose interrogations were videotaped, according to a government official with knowledge of the tapes.
The CIA made the decision to destroy the tapes "only after it was determined they were no longer of intelligence value and not relevant to any internal, legislative, or judicial inquiries," Hayden said.
But Rizzo was against the destruction of videotapes, a former intelligence official said Friday.
The ex-official, who did not want to be identified, told CNN that Rizzo didn't know they had been destroyed until it was already done.
Also Friday, two senior Bush administration officials told CNN that Harriet Miers -- who held a series of top posts at the White House starting in 2001 -- was aware of the tapes and told the CIA not to destroy them.
Miers became White House counsel in February 2005 and resigned in January.
The officials, who spoke on condition of anonymity because of potential investigations on the matter, said they believe this is "exculpatory" for the White House because it shows a top official had told the CIA not to destroy the tapes.
The officials also said the information about the tapes was not relayed to the president until this week.
Sen. Chris Dodd, D-Connecticut, said explanations of the events were "stretching credulity."
"There's something going on here," Dodd, a candidate for the Democratic presidential nomination, said on CNN's "The Situation Room."
"We're not getting the full story, hence the reason why there should be an investigation. It goes to the heart of our national security, our protection, our safety, our isolation in the world. That's why this is so important."
Another lawmaker also severely criticized the destruction.
Sen. Richard Durbin, D-Illinois sent a letter to Attorney General Michael Mukasey calling for an investigation into whether any laws were broken by "CIA officials who covered up the existence of these videotapes."
The Justice Department later said it had received Durbin's letter but would not comment other than to say it had begun gathering facts. E-mail to a friend
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