Of course it doesn't mean they are Jews! And why is the media being attacked on this? (I know, we all tend to have suspicions when it comes to the media, but...) How else are they supposed to describe these two scumbags if they don't know for certain whether they are Jews or Arabs? How many of you have your religion stamped on your driver's license or your passport? How about your political affiliations?
So we know they're Israeli nationals. That could certainly mean non-Jews. I'd be willing to bet that is exactly what they are. I don't see any need for retractions here. I'd be curious about further elaborations, though.