On September 11, 2001, Brokaw joined Katie Couric and Matt Lauer around 9:30 a.m., following the live attack on the South Tower of the World Trade Center, and continued to anchor all day, until after midnight. Following the collapse of the second tower, Brokaw observed: "This is war. This is a declaration and an execution of an attack on the United States." He continued to anchor coverage to midnight on the following two days. Later that month, a letter containing anthrax was addressed to him as part of the 2001 anthrax attacks. Brokaw was not harmed, but two NBC News employees were infected. In 2008, he testified before the Commission on Prevention of Weapons of Mass Destruction Proliferation and Terrorism about the anthrax attacks, publicly discussing his experiences for the first time in a detailed, day-by-day account.