Bavarian officials said on Sunday that the 18-year-old gunman who shot nine people dead in Munich had planned the crime for a year. The gunman visited the site of a previous school shooting in a German town which killed 15 people and took photographs.

Officials said that the shooter did not specifically choose his victims, adding that none of his classmates were targeted. The gunman purchased his weapon on the internet illegally. Officials also stressed that they have made a mistake in linking the gunman with the Norwegian far-right terrorist Anders Breivik, responsible for the 2011 Norway attacks.

Further investigation is underway for more details.