Former US treasury secretary Paul O'Neill dead at 84

Former US treasury sectary Paul O'Neill, who served under George W. Bush, died Saturday at the age of 84 after a battle with cancer, his alma mater Indiana University announced.

O'Neill, who died in Pittsburgh, was "known for his unflinching integrity, his data-driven approach to decision-making and his strong commitment to public service," IU said in a statement.

The straight-talking secretary lasted less than two years at the Treasury during Bush's first term in office -- he was fired after a public spat with the administration in December 2002.

He late became the subject and key source for Ron Suskind's book "The Price of Loyalty: George W. Bush, the White House, and the Education of Paul O'Neill," which offered a damning look at the Bush administration.

"Through my book he spoke truth to the world about no WMD in Iraq, Cheney's seizure of power and Bush's fecklessness," Suskind wrote on Twitter.

"He was a believer in truth -- that's what got him fired -- and a true American hero. Farewell old friend." Current Treasury Secretary Steven Mnuchin tweeted that O'Neill had served America "with distinction during challenging times."