BERLIN/FRANKFURT, July 23 (Reuters) - An 18-year-old German-Iranian believed to have acted alone killed nine people in a shooting spree with a pistol at a busy shopping centre in Munich on Friday evening.

Here are some facts about acquiring and owning a gun in Germany.

1. Germany has some of the "most stringent" rules around gun control in Europe, according to the U.S. Library of Congress. (https://www.loc.gov/law/help/firearms-control/germany.php#t1)

2. To own a gun in Germany, it is necessary to obtain a weapon licence for which applicants must generally be at least 18 years old and show they have they have a reason for needing a weapon.

3. German authorities can prohibit anyone who is dependent on drugs or alcohol or is mentally ill from obtaining a gun license. People under 25 have to undergo a psychiatric test. (https://www.gesetze-im-internet.de/waffg_2002/BJNR397010002.html)

4. After a teenager shot 15 people dead at a school in the southwestern town of Winnenden in 2009, Germany tightened the rules around firearms. Among other things, authorities were given greater authority to check whether guns were stored securely when not in use, and can make spot checks. (http://www.bmi.bund.de/DE/Themen/Sicherheit/Waffenrecht/Aenderungen-Waffenrecht-2009/aenderungen-waffenrecht-2009_node.html)

5. Almost 5.5 million firearms are owned privately in Germany by around 1.4 million people, according to data from the German Firearms Register in early 2013. Germany's population is about 82 million. (http://www.bva.bund.de/SharedDocs/Kurzmeldungen/DE/BVA/Sicherheit/NWR/2013-01-02_News_NWR_Inbetriebnahme11.html)

6. There are up to 20 million illegal firearms in Germany, the daily Frankfurter Allgemeine Zeitung cited experts in Germany as saying in January. (http://www.faz.net/aktuell/politik/inland/in-deutschland-gibt-es-bis-zu-zwanzig-millionen-illegale-waffen-14030574.html)

By comparison, website GunPolicy.org says between 270 million to 310 million legal and illegal firearms are owned by civilians in the United States, where the population is about 324 million. (http://www.gunpolicy.org/firearms/region/united-states)

7. The Federal Criminal Police Office said in its 2015 annual report that the use of firearms had been on a downward trend for years. In 2015 there were 4,289 cases of people being threatened with firearms - the lowest level since 1993. There were 4,711 cases of people or things being shot at in 2015, it said. (file:///C:/Users/U0148792/Downloads/pks2015Jahrbuch.pdf)

8. There were 57 gun homicides in Germany in 2015, up from 42 the previous year - compared with 804 in 1995, according to website GunPolicy.org (http://www.gunpolicy.org/firearms/region/germany)

(Reporting by Michelle Martin and Erik Kirschbaum in Berlin, Maria Sheahan in Frankfurt; editing by Mark Heinrich)

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