German police, which also involved Germany's GSG9 special operations police unit, walks past a locked rubbish bin outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, walks past a locked rubbish bin outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, walks past a locked rubbish bin outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

Doorbell buttons are pictured as German police, which also involved Germany's GSG9 special operations police unit, raid sites across the country, in a crackdown on human trafficking and forced prostitution in Bonn, Germany, April 18, 2018. REUTERS/Wolfgang Rattay

Doorbell buttons are pictured as German police, which also involved Germany's GSG9 special operations police unit, raid sites across the country, in a crackdown on human trafficking and forced prostitution in Bonn, Germany, April 18, 2018. REUTERS/Wolfgang Rattay

German police, which also involved Germany's GSG9 special operations police unit, wait outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, leave a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, holds a camera as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, leave a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, leave a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, leave a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, leave a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, enter a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, wait outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, wait outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, wait outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

German police, which also involved Germany's GSG9 special operations police unit, wait outside a building as they raid sites across the country, in a crackdown on human trafficking and forced prostitution in Maintal, south of Frankfurt, Germany, April 18, 2018. REUTERS/Kai Pfaffenbach

Members of German Federal Police (Bundespolizei) special unit GSG 9 together with firefighters demonstrate their skills during an emergency drill to practise their response in the case of a biological attack, at the "Fighting City" police training complex in Berlin, Germany October 11, 2017. REUTERS/Fabrizio Bensch

German Interior Minister Thomas de Maiziere speaks with members of the GSG 9 unit of Bundespolizei, Germany's federal police, during the opening of a new headquarters for special forces and anti-terror units in Berlin, Germany August 8, 2017. REUTERS/Hannibal Hanschke

A member of the GSG 9 unit of Bundespolizei, Germany's federal police, is pictured during the opening of a new headquarters for special forces and anti-terror units in Berlin, Germany August 8, 2017. REUTERS/Hannibal Hanschke

German Interior Minister Thomas de Maiziere speaks with members of the GSG 9 unit of Bundespolizei, Germany's federal police, during the opening of a new headquarters for special forces and anti-terror units in Berlin, Germany August 8, 2017. REUTERS/Hannibal Hanschke

Members of the GSG 9 unit of Bundespolizei, Germany's federal police, are pictured during the opening of a new headquarters for special forces and anti-terror units in Berlin, Germany August 8, 2017. REUTERS/Hannibal Hanschke

A road sign is pictured at the exit of the village where suspected accomplice of a neo-Nazi cell Andre E. was arrested by German special police unit GSG-9 in Grabow, south-west of Berlin, November 24, 2011. REUTERS/Fabrizio Bensch (GERMANY - Tags: CRIME LAW)

A road sign is pictured at the entrance of the village where suspected accomplice of a neo-Nazi cell Andre E. was arrested by German special police unit GSG-9 in Grabow, south-west of Berlin, November 24, 2011. REUTERS/Fabrizio Bensch (GERMANY - Tags: CRIME LAW)

A road sign is pictured at the entrance of the village where suspected accomplice of a neo-Nazi cell Andre E. was arrested by German special police unit GSG-9 in Grabow, south-west of Berlin, November 24, 2011. REUTERS/Fabrizio Bensch (GERMANY - Tags: CRIME LAW)

A general view shows a building where suspected accomplice of a neo-Nazi cell Andre E. was arrested by German special police unit GSG-9 in Grabow, south-west of Berlin, November 24, 2011. REUTERS/Fabrizio Bensch (GERMANY - Tags: CRIME LAW)

A general view shows a building where suspected accomplice of a neo-Nazi cell Andre E. was arrested by German special police unit GSG-9 in Grabow, south-west of Berlin, November 24, 2011. REUTERS/Fabrizio Bensch (GERMANY - Tags: CRIME LAW)

Members of GSG9 paintball team take a break during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

A member of GSG9 paintball team takes position during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

Members of GSG9 paintball team relax after a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

Members of GSG9 paintball team take up positions during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

Members of GSG9 paintball team shoot during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

A member of GSG9 paintball team stands before a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

A member of GSG9 paintball team sits during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

A member of GSG9 paintball team walks after he was shot during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

A member of GSG9 paintball team stands before a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

Members of GSG9 paintball team take up positions during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

Members of GSG9 paintball team take up positions during a training session in Rio de Janeiro March 2, 2008. The GSG9 paintball team was created a year ago by fanatics of the sport that named themselves after the counter-terrorism unit of the German Federal Police. REUTERS/Bruno Domingos (BRAZIL)

German Interior Minister Wolfgang Schaeuble talks to Ulrich Wegener, former chief of Germany's special unit GSG 9, during a commemoration for the victims killed by former West Germany's militant Marxist Red Army Faction RAF in Berlin October 24, 2007. German government representatives and relatives on Wednesday commemorated killed leading German establishment figures, including industrialist Hanns Martin Schleyer. REUTERS/Tobias Schwarz (GERMANY)

German special police unit GSG-9 patrol on the seaside of the venue of the G8 summit in Heiligendamm June 6, 2007. Leaders from the world's major industrialised nations meet in the Baltic resort of Heiligendamm on June 6-8 for a Group of Eight (G8) summit. REUTERS/Fabrizio Bensch (GERMANY)

Members of the special unit GSG 9 take part in a joint exercise demonstrating special forces reaction to a hostage taking situation at the German Federal Police in Sankt Augustin near Cologne April 27, 2007. Special forces from Germany, Denmark, Belgium, Austria and Czech Republic took part in the training situation. REUTERS/Alex Grimm (GERMANY)

Two members of the German special unit GSG 9 abseil from a helicopter during a joint exercise demonstrating special forces reaction to a hostage taking situation at the German Federal Police in Sankt Augustin near Cologne April 27, 2007. Special forces from Germany, Denmark, Belgium, Austria and Czech Republic took part in the training situation. REUTERS/Alex Grimm (GERMANY)

Two members of the German special unit GSG 9 overpower a mock hostage-taker during a joint exercise demonstrating special forces reaction to a hostage taking situation at the German Federal Police in Sankt Augustin near Cologne April 27, 2007. Special forces from Germany, Denmark, Belgium, Austria and Czech Republic took part in the training situation. REUTERS/Alex Grimm (GERMANY)

A mock hostage-taker is shot by members of the special unit GSG 9 during a joint exercise demonstrating special forces reaction to a hostage taking situation at the German Federal Police in Sankt Augustin near Cologne April 27, 2007. Special forces from Germany, Denmark, Belgium, Austria and Czech Republic took part in the training situation. REUTERS/Alex Grimm (GERMANY)

A marksman of the German special unit GSG 9 keeps watch from a roof, during a joint exercise demonstrating special forces reaction to a hostage taking situation at the German Federal Police in Sankt Augustin near Cologne April 27, 2007. Special forces from Germany, Denmark, Belgium, Austria and Czech Republic took part in the training situation. REUTERS/Alex Grimm (GERMANY)

German President Johannes Rau (L) smiles as he stands beside a
policeman of the special police unit of the German border police called
GSG9 in Sankt Augustin near Bonn March 12, 2002. President Rau visited
the unit to get information about standard of practice and know how of
the specialists. REUTERS/Juergen Schwarz

JS/JOH/AA

German President Johannes Rau (R) walks past a policeman of the special
police unit of the German border police called GSG9 in Sankt Augustin
near Bonn March 12, 2002. President Rau visited the unit to get
informations about standard of practice and know how of the
specialists. REUTERS/Juergen Schwarz REUTERS

JS/JOH

Anti terrorist police from the special unit GSG-9 arrest rioters who were holding a prison warden hostage for some 22 hours July 25. Police said they ended the mutiny of mainly Algerian refugees whose applications for political asylum had been rejected

Anti terrorist police from the special unit GSG-9 arrest one of the 39 rioters who were holding a prison warden hostage for some 22 hours July 25. Police said they ended the mutiny of mainly Algerian refugees whose applications for political asylum had been rejected