A time bomb exploded Friday in a car belonging to a Greek prison director, smashing windows and injuring a passerby, radio reports said according to dpa. The bomb was left under the car used by Maria Stefi, the director of the high-security Korydallos prison, located in the Athens suburb of Dafni. An unidentified individual called a Greek news website saying the bomb would go off in 20 minutes. A woman was slightly injured by the broken glass. No one has claimed responsibility for the explosion.