An officer responded to a BART property near the station on the report of two subjects setting up what appeared be a tent. One of the subjects was described as a White male wearing a black sweatshirt and a brown T-shirt. No description of the second subject was provided. On arriving at the property, the officer contacted the lone white male who matched the earlier reported description. The officer performed a criminal history check of the subject and learned he was not in compliance with his sex registrant status. The officer placed the subject under arrest for the violation, and a sergeant approved the arrest. The subject was then booked into the county jail.