Under cover MBTA police continue to nab alleged criminals during fare blitzes across the transit agency.


Over the past week, transit police have issued 71 fare evasion citations, and one of them ended with the arrest of a wanted man - not an uncommon occurrence lately.


While staked out at Andrew Square station last week, transit police arrested a man who they say was an unregistered sex offender with several warrants.


James Hagan, 27, of Randolph, was arrested after transit police said they witnessed him "piggyback" behind a paying customer at 11:30 a.m. on Aug. 19.


When officers stopped Hagan to issue a $50 ticket, they discovered that he had warrants out for attempt to commit a crime out, driving with a suspended license, using a motor vehicle without authority and leaving the scene of property damage.


Hagan was also found to be an unregistered sex offender, a violation of state law.