German police arrested the suspected former courier of U.S. army spy Clyde Lee Conrad on Wednesday at the Frankfurt airport, according to the Federal Prosecutor's office. Police have been looking for Sandor K. (whose full name was not released), a Swedish citizen, for more than 10 years. The Hungarian native is suspected of carrying documents Conrad smuggled out of American army bases in Germany to the Hungarian intelligence agency. Conrad worked as a spy while serving in Germany from 1968 to 1985. He was arrested and sentenced to life in prison in 1990. K. is being charged with serving as an accomplice to treason.