Two officers of the police’s motorcycle-bound Z unit and five special guards employed to patrol the perimeter of Attica police headquarters in central Athens yesterday became the focus of an internal investigation following the theft from the back entrance to the premises of a car that had been confiscated earlier by drug squad officers. According to police, the car was stolen early on Sunday by a couple who are believed to have had a spare set of keys. The couple reportedly arrived at the police headquarters by taxi, got into the vehicle and drove off unseen by any of the seven officers on duty in the area. The car was found later abandoned in the northwestern suburb of Aghioi Anargyroi. Police said they had identified the couple though they had yet to trace them by late last night. The officers, charged with dereliction of duty, were released pending the outcome of the internal probe.