Police in Greece's capital were searching for a gunman who opened fire at a social security office and a courthouse on Tuesday, wounding several people. Greece's public broadcaster ERT reported that the alleged gunman was an 89-year-old man and a police operation was underway to locate the armed man. Rescue teams leave premises of courthouse in central Athens Image: Sotiris Dimitropoulos/Eurokinissi/REUTERS What we know so far  Police said the suspect opened fire with a shotgun at a branch of Greece's EFKA social security agency, wounding an employee in the leg. The gunman then traveled by taxi to a court building, where he fired several shots inside, lightly wounding four female court clerks, police and court officials said. The motive for the shooting was unclear. The gunman had fled the scene but reportedly left letters with documents after the shooting at the courthouse, ERT reported.…