Section 230.4 - Arrest and investigative powers of criminal investigators(a) Under the authority of 18 U.S.C. 3061 , criminal investigators employed by the Office of Inspector General are authorized to perform the following functions in connection with their official duties:(1) Serve warrants and subpoenas issued under the authority of the United States;(2) Make arrests without warrant for offenses against the United States committed in their presence;(3) Make arrests without warrant for felonies cognizable under the laws of the United States if they have reasonable grounds to believe that the person to be arrested has committed or is committing such a felony;(5) Make seizures of property as provided by law.(b) Administrative subpoenas may be served by delivering a copy to a person or by mailing a copy to the person's last known address. For the purposes of this provision, delivery of a copy includes handing it to the party or leaving it at the party's office or residence with a person of suitable age and discretion employed or residing therein. Service by mail is complete upon mailing. 67 FR 16025 , Apr. 4, 2002, as amended at 71 FR 12285 , Mar. 10, 2006