FRANKFURT - A Kosovo-Albanian man who killed two US airmen and wounded two others in a gun attack at Frankfurt airport last March was sentenced to life in prison by German court on Friday.Arid Uka, a 22-year-old who was raised in Germany, had confessed to the attack and said he acted after seeing a video apparently showing US soldiers raping Muslim women.Wearing a black hooded top, he smiled when police removed the handcuffs after bringing him into the Frankfurt courtroom, then sat with eyes downcast as Judge Thomas Sagebiel read out a detailed chronology of the attack."Yes, this is indeed the first Islamic-motivated terror strike to have happened in Germany," the judge said.