Patrick Daniel Tillman (November 6, 1976 - April 22, 2004) was a professional American football player in the National Football League (NFL) who left his sports career and enlisted in the United States Army in June 2002 in the aftermath of the September 11 attacks. His service in Iraq and Afghanistan, and subsequent death, were the subject of much media attention. Tillman joined the Army Rangers and served several tours in combat before he was killed in the mountains of Afghanistan. At first, the Army reported that Tillman had been killed by enemy fire.

On April 24, 2007, Specialist Bryan O'Neal, the last soldier known to see Pat Tillman alive, testified before the House Committee on Oversight and Government Reform that he was warned by superiors not to divulge information that a fellow soldier killed Tillman, especially to the Tillman family. Later, Pat Tillman's brother Kevin Tillman, who was also in the convoy traveling behind his brother at the time of the 2004 incident in Afghanistan but did not witness it, testified that the military tried to spin his brother's death to deflect attention from emerging failings in the Afghan war.  On July 13, 2007, Henry Waxman and Tom Davis, the leading members of the House Committee on Oversight and Government Reform, revealed that the Bush administration and the Pentagon had withheld key documents relating to Tillman's death and denied any new document release request from Congress citing executive privilege.  On August 13, 2007, the Associated Press reported that on behalf of VoteVets, twenty U.S. military veterans who fought in Iraq and Afghanistan asked the NFL commissioner, Roger Goodell, to help secure the release of all documents relating to the death of Pat Tillman.  On July 14, 2008, the House Committee on Oversight and Government Reform released a proposed report titled "Misleading Information from the Battlefield: The Tillman and Lynch Episodes". The committee stated that its "investigation was frustrated by a near universal lack of recall" among "senior officials at the White House" and the military. It concluded:  The pervasive lack of recollection and absence of specific information makes it impossible for the Committee to assign responsibility for the misinformation in Specialist Tillman's and Private Lynch's cases. It is clear, however, that the Defense Department did not meet its most basic obligations in sharing accurate information with the families and with the American public.

Answer the following question by taking a quote from the article: How did he die?
testified that the military tried to spin his brother's death to deflect attention from emerging failings in the Afghan war.