An intern for Sen. Ted Cruz, R-Texas, was arrested this week after U.S. Capitol Police discovered unregistered ammunition in the intern’s vehicle.

U.S. Capitol Police told the Washington Examiner that Scott Frantz, 20, was arrested after officers responded to a report on Monday afternoon regarding a “dispute” between Frantz and another person in a vehicle near Capitol Hill.

Officers noticed there were shotgun shells in the vehicle, and charged Frantz with possession of unregistered ammunition. D.C. law requires that firearms and ammunition be registered.

According to CNN, Frantz was an intern for Cruz and was subsequently placed on leave following the incident.

A spokesperson for Cruz’s office told CNN that his “office does not comment on pending law enforcement or personnel matters."