“It is very important to be firm on this. I think, for example, that we should have a debate at the European level connected to the idea that was raised some time ago to set up a European institute to train imams,” he told the media.

Michel said “this message of tolerance, openness can be conveyed at the European level … to ensure that the primacy of civil law is accepted,” he said.

“Online messages glorifying terrorism must be quickly removed. There must be no impunity for terrorists and those praising them on internet,” he said later in a tweet.

Last Monday’s shooting was the first major attack of its kind in Austria for decades and the first blamed on a jihadist.

The gunman was identified as Kujtim Fejzulai, 20, a dual Austrian-Macedonian national who was convicted and imprisoned last year for trying to go to Syria to join IS.

“We think that this terrorist threat is a fundamental, grave, serious threat against the values” of modern Europe, Michel said, adding that “we have no intention of showing any weakness or laxity.”