Updated: 3:07 p.m.A Capitol Police officer was arrested Sunday in Arlington, Va., after a woman arrived home to find him passed out on her bed.Arlington Police spokeswoman Detective Crystal Nosal said Thomas Patrick McMahon was intoxicated but not armed. The woman told police she found him at about 1 a.m., when she returned to her apartment on North Randolph Street.McMahon, 34, was charged with unlawful entry. Nosal said she did not know why he was in the home, but added that the case is closed and is now being handled by the courts.McMahon — who is part of an elite tactical unit — appears to have run into trouble before. According to Fairfax County Police records, a 30-year-old Capitol Police officer fired his handgun on Jan. 30, 2006, from inside his house in the 2100 block of Whisperwood Glen Lane in Reston, Va. The bullet went through the front door and hit a 51-year-old cab driver who was standing outside his cab. The bullet hit him in the “lower body,— and his injuries were not life-threatening.Thomas P. McMahon lives at 2178 Whisperwood Glen Lane, according to whitepages.com.Capitol Police spokeswoman Sgt. Kimberly Schneider said the department is “unable to confirm— that McMahon was involved in the 2006 incident. For Sunday’s arrest, McMahon is on paid administrative leave pending the outcome of the criminal charges, she said. The department will conduct an internal investigation once the outcome of the charges is known.McMahon has been with the Capitol Police since 1998 and is part of the Containment Emergency Response Team, a tactical unit that is trained to respond to terrorist attacks and other threats to the Capitol.