No where in the Torah does it say to eat pork or drink blood. Actually it says both are not forbidden. Thus it is possible a Jew did something, wrong but he was not following Judaism. Next, their might be a sicko in any group. But if there was a sicko that drank blood that was Jewish beleive me there are sickos that are Christian that also did that. Look on google for modern day vampires, see how many Jews you see on those websites and see how many christians you see on them. Nevertheless, the whole story about Jews drinking blood? I am sure it is false.
Abbas to urge UN to pressure Israel to permit entrance to Palestinian refugees from Syria (Haaretz)
from the article: And supposing they did drink blood?