SCHOOL - MASSACRE IN AUSTRIA – IS IT POSSIBLE?

In the last few years there were several massacres at schools in Germany and in the USA. The students who committed the crimes were so angry with their teachers and their school principals that they came back to school and to kill them. Several students died at such massacres, too.
But is it possible that such terrible things can also happen in a peaceful country like Austria? Some people think in Austria only the parents are the ones who become aggressive when their children have problems in school. Maybe this is true at my school, where there are only harmless st...