Remembered for serving as both a Special Agent in the Federal Bureau of Investigation and the Director of Security for the World Trade Center, this counter-terrorism official was tragically killed in the September 11, 2001 attacks on the World Trade Center.
While studying at Washington, D.C.'s American University, he secured a tour guide position at the F.B.I. After completing graduate work in forensics at George Washington University, he became an F.B.I. agent.
The subject of a television documentary titled The Man Who Knew, he was also the lead character in a miniseries called The Path to 9/11. In addition, the book The Man Who Warned America discusses his counter-terrorist legacy.
A native of Atlantic City, New Jersey, he later lived and worked in Washington, D.C. and New York City.
He first became aware of al-Qaeda leader Osama bin Laden while investigating the mid-1990s bombing of Saudi Arabia's Khobar Towers.