Confirmed.
The one that has been arrested said to a witness (can't confirm is it was a police officer or someone on the scene) that he is a muslim and did this because because of Israel. I still haven't seen anything to absolutely confirm this but I'm back at work now and we have tv's on the floor and on fox news, they are saying the same thing. Muslim who did the shooting because of Israel.
I live in Seattle and work downtown. This happened just as I was getting out of work and as I was walking to a bar to meet friends, ambulances and police cars were barreling down the streets downtown towards where this occured like crazy, but didn't know what was going on. Then in the bar, I saw the news report hit on on the tv what had happened.