The U.S. is condemning instances of religious intolerance that are inflaming tensions in Ukraine.

Secretary Of State John Kerry (Mark Wilson, Getty Images)

Among them is the distribution of leaflets demanding that Jews in eastern Ukraine identify themselves.

Secretary of State John Kerry says the leaflets are, quote, "grotesque and beyond unacceptable." He also denounces apparent threats to members of the Russian Orthodox Church from members of the Ukrainian Orthodox Church. Kerry says no such behavior can be tolerated. He's in Geneva for talks on Ukraine

The anti-Semitic leaflets recall the Nazi-era persecution of Jews. U.S. officials in Washington say they've appeared recently in the eastern Ukrainian city of Donetsk amid pro- and anti-Russian protests.

The State Department says it is looking into who is responsible but takes the threat seriously no matter who is behind the leaflets.

New Jersey Congressman Leonard Lance, co-chairman of the House GOP's Israel Caucus, said Thursday he was "appalled" at the reports of Jewish Ukrainians being forced to register their names and property.

"Today’s news harkens us back to some of the worst times in human history," Lance said,  "I immediately call for the world community to denounce these tactics and allow the Jewish people to practice their faith freely.”

The NJ101.5 News Staff also contributed to this story.