NCTC maintains the US Government’s authoritative database on terrorist¹ attacks compiled exclusively from open source data, known as the Worldwide Incidents Tracking System (WITS). This database is publicly available at www.nctc.gov, and provides an accessible, Internet-based database to a variety of consumers, including the government, police departments, first responders, military, academia, the press, and the public. WITS allows users to filter and sort attack data by a broad range of characteristics, browse attack records, and derive statistics on terrorism around the world. Using a variety of searches, the public can query the database to research activity by region and determine, for example, how many improvised explosive device (IED) attacks occurred in Afghanistan in 2010 (1,129), how many incidents in 2010 were suicide attacks (264), and the category of victims that were frequently targeted (civilian, military, political).

To be included in the database, terrorist attacks must have been premeditated, politically motivated, and executed on noncombatants. WITS does not include spontaneous hate crimes not intended to cause mass casualties, or failed or foiled attacks or hoaxes. A complete explanation of the WITS methodology is available on the Web site.

NCTC also provides the US State Department with statistical data derived from the WITS database on the number of individuals killed, injured, or kidnapped by terrorist groups. This information is used to help complete the congressionally mandated Country Reports on Terrorism, the US Government’s annual authoritative report on terrorism incidents.

The WITS database lists 73,866 incidents from 1 January 2005 through 31 December 2010.