The leadership in Justice and the FBI anticipated the worst and decided to act independently, the special operations forces lurking behind the scenes.
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The contingency units meeting on January 3 included the FBI's Hostage Rescue Team, the FBI's national "Render Safe" team, an FBI SWAT team from the Baltimore Field Office, Special Response Teams from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF), and the U.S. Marshals Service Special Operations Group.
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On the morning of January 6, most of these forces staged closer to downtown Washington, particularly after intelligence was received indicating a possible threat to FBI headquarters building or the FBI's Washington Field Office. FBI tactical teams arrived on Capitol Hill early in the day to assist in the collection of evidence at sites—including the Republican and Democrat party national headquarters—where explosive devices were found. FBI SWAT teams and snipers were deployed to secure nearby congressional office buildings. Other FBI agents provided selective security around the U.S. Capitol and protection to congressional members and staff.
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A tactical team of the Hostage Rescue Team was one of the first external federal agencies to actually enter the Capitol after protestors breached the building.