Hat tip Vlad Tepes
In the US since 9-11, we have had a handful of attacks against Sikhs including a deadly attack by one gunman in Wisconsin. These attacks have been blamed on a mistaken assumption by the attackers that the Sikhs were, in fact, Muslims. That has not been positively confirmed. (The Wisconsin attacker died in the assault.)
In Germany, an Essen Sikh temple was the object of a bombing. The three perps have just been sentenced by an Essen court. They are Muslims.