[A Turkish military officer is transferred to a court hall in the city of Alexandroupolis, northern Greece, Thursday, July 21, 2016. Eight Turkish military personnel who fled to Greece a board a helicopter during an attempted coup in their country are testifying in court during their trial on charges of entering Greece illegally. Turkey is seeking their return to stand trial for participation in Friday’s coup attempt. The eight deny any involvement and have applied for asylum, saying they fear for their lives if returned. (Antonis Pasvantis/InTime News via AP)]ATHENS, Greece (AP) — The Turkish military helicopter that landed in the Greek border city of Alexandroupolis just as an attempted coup was being quashed in Turkey has turned into one of the toughest diplomatic challenges to date for Greece's relatively inexperienced government.