Muslims kill 4 jews in a synagogue--CNN graphic on story reads "attack on *mosque*

The Grubering mainstream media frequently express their sense of superiority by saying they have "layers and layers of fact-checkers and editors" who ensure they don't make mistakes. 

Really?  Yesterday two Muslim males entered a synagogue in Jerusalem and killed four jews.  CNN ran a brief video clip of an interview with a witness, with a large graphic saying

DEADLY ATTACK ON JERUSALEM MOSQUE

Ah yes.  What would CNN and the rest do without all those fact-checkers.