(Corrects the word shot to shut)
Ahmet Yıldırım / Berlin, March 17 () - The German Embassy and Consulate as well as two German schools in Istanbul and Ankara were shut due to a "concrete tip-off" for a security threat.   The threat to German institutions in Turkey was being taken very seriously, said Foreign Minister Frank-Walter Steinmeier in a press statement in Berlin.   "Yesterday evening, some very concrete indications - to be taken very seriously - reached our security services, saying that terror attacks against German institutions within Turkey were being prepared" Steinmeier said on March 17.   "Protecting German citizens and the people working and learning in these establishments must now take precedence" he added.   The security measures within German institutions will be boosted Steinmeier explained, while calling on citizens to follow up travel advisories in the next days.