A German-Iranian teenager acquired the semi-automatic pistol he used to kill nine people in Munich on the dark web and did extensive research on mass shootings, Bavaria's interior minister Joachim Herrmann (CSU) tells the B24 broadcaster.
The 9mm Glock handgun was smuggled into Germany and sold illegally to 18-year-old killer Ali Sonboly. The serial number on the weapon had been erased but police sources have revealed the firearm carried a certification mark from Slovakia.
It is believed the weapon used to kill nine people on Friday was a replica that had been converted to fire live ammunition.
Police seized his computer from the home he shared with his parents and younger brother.
By examining his hard disk they will be able to find out where the gun was purchased from and most likely who was involved in its handling on its route from Slovakia to Germany.
The 18-year-old had a copy of the manifesto of Norway attacker Anders Breivik saved on his computer and travelled "within the past two years" to the scene of a 2009 school shooting in the southern German town of Winnenden, Joachim Herrmann tells the broadcaster.
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German officials on Sunday called for the country's gun laws to be reexamined, two days after a German-Iranian teenager armed with a semi-automatic pistol mowed down nine people before turning the gun on himself.
The number of people injured rose to 35 after a deadly rampage at a Munich shopping centre allegedly by a teenager obsessed with mass shootings, German police said Sunday.
German police believe that the lone, teenaged German-Iranian gunman who shot dead 10 people, including himself, in Munich was inspired by the massacre in Norway five years ago of 77 people by Anders Behring Breivik.
A gunman suspected of carrying out a terrorist shooting in Munich was an 18-year-old German-Iranian man, police chief Hubertus Andrae said Friday, adding that the motive for the crime is not known.