Well, look what happened with the Belgian Mosque:

Azzedine Laghmich, an official at the mosque, told AFP the attacker was “a Salafist,” who sprayed petrol inside the mosque before setting it alight and shouting Sunni slogans on his way out — cries related to the conflict in Syria.

“All the eyewitness accounts said so,” Laghmich added.
Isabelle Praile, another senior official in Belgium’s organized Muslim community, said the Rida mosque “had already been placed under police protection several years ago,” citing direct threats from members of the ultra-conservative Salafist movement.