Lawyers for a detainee held at the Navy brig in Charleston, S.C., allege in court papers to be filed today that their client was systematically abused and that he was told there were cabinets full of videotapes depicting his treatment at the hands of the FBI and the Defense Intelligence Agency.

Ali al-Marri, who has been in U.S. custody since his arrest in 2003, is seeking to have the conditions of his detention reviewed by a federal court and wants to be removed from isolation, where he has remained without charge for years. His allegations of being videotaped while he was mistreated could add to an uproar over CIA admissions that the agency videotaped detainees who were waterboarded and then destroyed the tapes.

The Defense Department has been reviewing its videotaping efforts in detention facilities since the CIA's revelations, and officials have been saying for months that there were few, if any, videotapes of interrogations that ever existed. Officials at the military detention facility at Guantanamo Bay, Cuba, acknowledged inadvertently destroying years' worth of video images of its operations as part of the routine overwriting of surveillance video but have not ruled out that interrogators kept at least some videotapes of interrogations.

The New York Times reported last night on its Web site that defense officials have turned up about 50 videotapes related to interrogations of Marri and Jose Padilla, another suspect held at the Navy brig. Donald Black, a spokesman for the Defense Intelligence Agency, said yesterday that one tape depicted Marri being gagged with duct tape. But he said the move was prompted by Marri's disruptive behavior, adding that there was no evidence on the video of abuse.

"Marri was chanting very loudly and was being disruptive," Black said. "It was determined that he should be quieted up, and if he didn't they were going to put tape over his mouth. When Marri was told this he got even louder."

Jonathan Hafetz, an attorney for Marri, said yesterday that his client has been forced to endure stress positions, sensory deprivation, and threats of violence or death.

"On several occasions, interrogators stuffed Mr. Almarri's mouth with cloth and covered his mouth with heavy duct tape," according to the legal filings to be presented to the U.S. District Court in South Carolina, which refer to the apparently videotaped incident. "The tape caused Mr. Almarri serious pain. One time, when Mr. Almarri managed to loosen the tape with his mouth, interrogators re-taped his mouth even more tightly. Mr. Almarri started to choke until a panicked agent from the FBI or Defense Intelligence Agency removed the tape."

Black said the Marri interrogation involved defense officials and members of another agency. A U.S. source familiar with the tapes identified the other agency as the FBI.

The DIA official said the tapes were made in part to ensure that interrogations were being carried out according to Pentagon rules. Most of the tapes were routinely destroyed after transcripts of the interviews were made, Black said.

Staff researcher Julie Tate contributed to this report.

© 2008 The Washington Post