The weird thing is that this guy could be a nontrinitarian Christian:

Asked whether he was ever victimized by a Christian, he replied no, and said his family is Christian and that he had a good childhood.

He could be a Judaist, but the issue is that murder is one of the three cardinal sins that Judaists must never commit, even at risk of death, and even if the victim’s beliefs are totally at odds with Judaism. This does not eliminate the possibility, though. In any case, I can imagine this news leading to a growth in anti-Judaism.