Teenager arrested after two girls seriously injured in attack at Bavarian school
German Interior Minister Alexander Dobrindt told reporters near the scene of the attack that the suspect was a "former pupil at the school" and a citizen of another EU country.
Dobrindt said it seemed the suspect was suffering a "mental health emergency" and that he had already been receiving treatment.
The attacker had been carrying knives and a firearm, which he fired without injuring anyone.
After the firearm malfunctioned he used a knife to injure two schoolgirls, Dobrindt said.
"The teachers and the police officers who had by then arrived on the scene were able to overpower the suspect," he added.
Police said the two girls were both aged 13 and were taken to hospital with serious injuries.
Following updates on their treatment, police spokesman Michael Spessa told reporters "we can cautiously say that the lives are not in danger".
A large group of armed police and a fire engine could be seen outside the school late on Wednesday afternoon and a helicopter was flying above Schongau, a town of 12,000 people just north of the Alps.
Dobrindt said it looked like the crime was a "rampage committed by a lone perpetrator" and the two girls appeared to be "random victims, according to our assessment, who happened to be in his path at that time".
The perpetrator appeared to have deliberately targeted the Welfen grammar school in the town of Schongau in a suspected "rampage", a police spokeswoman told reporters.
The alarm was raised at around 12:50 p.m., prompting a large-scale emergency response. More than 15 police vehicles were dispatched to the school in Schongau, a town of just over 12,000 residents southwest of Munich.
Police initially said several people were injured. Investigators continue to assess the extent of the injuries and the circumstances surrounding the attack.
Officers urged members of the public to stay away from the area. A reception centre has been established at a nearby fire station for parents, relatives and students seeking information.
Welfen High School, located near Schongau's historic centre, has approximately 800 students and more than 80 teachers. The incident remains under investigation.