BERLIN - Another German couple is believed to have been detained in Turkey this weekend and one of the individuals remains in police custody, while the other has been barred from leaving the country, a German foreign ministry spokesman said on Monday.Spokesman Martin Schaefer told a news conference that Germany had no official information on the arrests that occurred on Sunday in Istanbul, but said the random nature of continued detentions by Ankara was cause for "the utmost concern.""The nightmare continues that is facing so many German citizens who wanted to do nothing but spend their vacation in Turkey," Schaefer. "It can hit anyone who thinks about entering Turkey. One doesn't believe to be in danger, but suddenly one is in a Turkish prison."