He towards the suspect and helped to prevent things from getting even worse, police spokesperson Rainer Dionisio told Austria's public broadcaster ORF.
You can receive breaking news alerts on a smartphone or tablet via the Sky News app.
Police said it wasn't certain the suspect had been acting on his own or with other people, and so they are continuing to look for potential further suspects.
A man has stabbed five people in southern Austria, killing a 14-year-old boy.
The 23-year-old man attacked five passersby in Villach on Saturday afternoon, according to police.
