Austrian police search for answers after mass shooting in school

Austrian authorities were searching on Wednesday for answers to why a 21-year-old gunman shot 10 people in a rampage at his former high school before killing himself, one of the worst outbreaks of violence in the country's modern history.

Police said the man, armed with a shotgun and a pistol, acted alone. They are scouring his home and the internet for clues to why he opened fire on the school in Austria's second city of Graz on Tuesday, before shooting himself in a bathroom.

Police added that a pipe bomb found at his home was not functional.

Some Austrian media have said the young man, who has not been identified, apparently felt bullied, though police have yet to confirm this. Austrian authorities said the suspect never completed his studies at the school.

He left a farewell note that did not reveal the motive for the attack, police said.

Franz Ruf, director general of public security, said investigations into the motive were moving swiftly. "We don't want to speculate at this point," he told national broadcaster ORF on Tuesday night.

Around 17 minutes elapsed between the first emergency calls received by police about shots being fired at the school and the scene being declared safe, Ruf said.

Details of the attack have emerged slowly.

Austrian police said victims were found both outside and inside the school, on various floors. About a dozen people were injured in the attack, some seriously.

Austria declared three days of national mourning, with the shootings prompting a rare show of solidarity among often bitterly divided political parties. Parents of pupils and neighbours of the school struggled to make sense of the event.

Hundreds came together in Graz's main square on Tuesday evening to remember the victims. Others left flowers and lit candles outside the school. Dozens also queued to donate blood for the survivors.