Investigators from the Justice Department allegedly found more than a dozen secretly recorded videotapes of the Mr Warren performing sex acts with other women. An official said one woman appeared to be in a "semi-conscious state".
Both the women who came forward to complain and made sworn statements are Muslim, and the case could spark a strong reaction in the Arab world. One of the women said she met the him at the bar in the American embassy before going to his residence, where she was drugged.
Algiers is one of the most sensitive posts in the agency, as it works closely with local intelligence services against a branch of al-Qaeda that has been responsible for major bombings, including an attack in the capital last August that killed 48 people.
The CIA refused to confirm that the investigation was taking place, but a spokesman said: "I can assure you the agency would take seriously, and follow up on, any allegations of impropriety." ABC's sources said the investigation had expanded to Egypt where the officer, who has not been named, served previously.