28 CFR §511.18

1. (a)You may be arrested and detained by Bureau staff anytime there is probable cause indicating that you have violated or attempted to violate applicable criminal laws while at a Bureau facility, as authorized by 18 U.S.C. 3050.
2. (b)“Probable cause” exists when specific facts and circumstances lead a reasonably cautious person (not necessarily a law enforcement officer) to believe a violation of criminal law has occurred, and warrants consideration for prosecution.
3. (c)Non-inmates arrested by Bureau staff under this regulation will be physically secured, using minimally necessary force and restraints, in a private area of the facility away from others. Appropriate law enforcement will be immediately summoned to investigate the incident, secure evidence, and commence criminal prosecution.