WASHINGTON - Political debate over whether Bush administration interrogation practices had helped find Osama bin Laden heated up on Thursday when Senator John McCain said torture of detained militants did not help locate the al-Qaida leader.

McCain said CIA Director Leon Panetta had told him the trail to bin Laden did not - as some former Bush aides have asserted - begin with information from Khalid Sheikh Mohammed, the self-professed Sept 11 mastermind who the US government says was "waterboarded" 183 times.

McCain, the Republican Party's 2008 presidential candidate said he wanted to clear up "misinformation" that could make Americans think harsh treatment of prisoners was acceptable.

"In short, it was not torture or cruel, inhuman and degrading treatment of detainees that got us the major leads that ultimately enabled our intelligence community to find Osama bin Laden," McCain, who himself suffered torture as a prisoner during the Vietnam war, said in the Senate.

His statements were backed up by Senate Intelligence Committee Chairwoman Dianne Feinstein, whose staff has been conducting an investigation of US interrogations of "high-value" detainees in the aftermath of the Sept 11, 2001, attacks on New York and Washington.

Feinstein said the CIA had "significant reporting" on an al-Qaida courier close to bin Laden that "was acquired independent of the CIA detention and interrogation program." She also said a CIA detainee who produced other critical information had done so before being subjected to "enhanced interrogation techniques."

Current and former national security officials have told Reuters, however, that while Mohammed did not provide information that initiated the successful hunt for bin Laden, his responses to questions about the al-Qaida courier helped convince intelligence officials the courier might be key to finding bin Laden.

Claims and counter claims

McCain's remarks ran counter to claims by some veterans of former President George W. Bush's administration that harsh interrogation techniques used early in that administration were critical to the operation that tracked down and killed bin Laden.

The CIA suspended the use of waterboarding, or simulated drowning, in 2004 after it was used on Mohammed and only two other detainees. Bush later wound up the agency's interrogation program and President Barack Obama banned harsh interrogation techniques soon after taking office in 2009.

McCain said none of the three detainees who were waterboarded provided the real name of bin Laden's courier and Mohammed gave false information about the courier's whereabouts and role.

The best intelligence about bin Laden's courier, Abu Ahmed al-Kuwaiti, was obtained through "standard, noncoercive means," said McCain.

However, former US Attorney General Michael Mukasey said Mohammed had disclosed the courier's nickname, "along with a wealth of other information, some of which was used to stop terror plots then in progress."

Saxby Chambliss, the ranking Republican on the Senate Intelligence Committee, said the debate over whether "enhanced" interrogations really produced breakthroughs in the hunt for bin Laden is "unlikely to ever be settled."