WASHINGTON — A former CIA officer who participated in the capture and questioning of the first Al Qaeda terrorist suspect to be waterboarded said yesterday that the harsh technique provided an intelligence breakthrough that “probably saved lives” but that he now regards the tactic as torture. Zayn Abidin Muhammed Hussein Abu Zubaida, the first high-ranking Al Qaeda member captured after the September 11, 2001, attacks, broke in less than a minute after he was subjected to the technique and began providing interrogators with information that led to the disruption of several planned attacks, John Kiriakou, who served as a CIA interrogator in Pakistan, said.

Mr. Abu Zubaida was one of two detainees whose interrogation was captured in video recordings that the CIA later destroyed. The recent disclosure of the tapes’ destruction ignited a recent furor on Capitol Hill and allegations that the agency tried to hide evidence of illegal torture. “It was like flipping a switch,” Mr. Kiriakou said. He is the first former CIA employee directly involved in the questioning of “high-value” Al Qaeda detainees to speak publicly.