The 18-year-old gunman who opened fire at Heidelberg University, killing one person and wounding three others before killing himself, had bought three weapons about a week ago in Austria, German police said on Wednesday, Trend reports citing Euronews.
Two of these weapons were seized at the scene, along with around 150 rounds of ammunition.
The third weapon, a rifle, was found by Austrian police in a room that the man, who was not identified by name in line with German privacy rules, had rented during his stay in Austria, Heidelberg police said in a statement.
Police say the German man — who was a biology student at the university — purchased the two weapons used in the attack from a weapons dealer and the third from a private individual, both in Austria.
The precise motive for the attack is still being investigated, but the suspect was known to have suffered from a psychological illness in the past.
"It cannot be ruled out that a mental illness of the suspect could have been the cause of the crime," the police statement said.
Investigators are also following up on indications that the suspect was a previous member of a far-right party, which he is said to have left in 2019, when he was still a minor.
Police identified the slain woman as a 23-year-old German.
Those who suffered minor wounds were two German women, aged 19 and 20, and a 20-year-old German-Italian man.
The shooting sparked a massive police response, with more than 400 officers sent to the scene.
Heidelberg, which hosts one of Germany's best-known universities, is located south of Frankfurt and has about 160,000 residents.