A gunman believed to be a student on Monday opened fire at a German University, killing one person and injuring three others.

Voice of America reports that the suspect opened fire during a lecture at the University of Heidelberg in southwestern Germany. 

Confirming the development, Siegfried Kollmar, the regional police chief identified the gunman as an 18-year-old biology student at the university.

He disclosed that the suspect, who has no previous police record, sent a text message to his father before carrying out Monday’s shooting.

Mr Kollmar told journalists that the suspect in the text messages mentioned that “people will be punished.”

Disclosing that the motive behind the attack was still being investigated, the police chief revealed that the suspect was known to have suffered from a psychological illness in the past, he added.

The police, however, said that the suspect appeared to have acted on his own accord.

“We assume that there was only one perpetrator. At this stage we see no further danger to the public,” police said.

The suspect who was reported to have dangerous firearms in his possession used a rifle during the attack.