Updated

Jewish leaders in the U.S. expressed grave concern Friday for Jews living in Ukraine – and Europe in general – after fliers were distributed in the eastern city of Donetsk telling Jews to register themselves with pro-Russian separatists, pay a fee and declare all property holdings.

The precise origin of the leaflets has been called into serious question, and the Russian separatist being blamed has denied any responsibility -- suggesting the documents were spread as a ploy to vilify his side in the Russian-Ukrainian conflict. Still, Jewish leaders say the fact these pamphlets were even distributed, some 70 years after the Holocaust, has a chilling effect on Jewish communities worldwide.

"As a Jew, what impacts me is how the anti-Semitism that prevailed in that part of the world seems to still be in the gut of some people in that community," said Jack Rosen, president of the American Jewish Congress.

"Sixty eight years hasn’t changed much," said Rosen, whose parents were Holocaust survivors.

"Finding the person responsible does not end the problem," Rosen stressed. "Why weren’t there major public outcries against it in that part of the world? Few came to the forefront to condemn it."

The U.S. government promptly denounced the fliers – with U.S. Secretary of State John Kerry calling the leaflets "grotesque" and "beyond unacceptable." The documents reportedly were handed out earlier this week to Jewish residents of Donestk, Ukraine, by masked men holding the Russian Federation flag. The leaflets were distributed as Jewish worshippers were leaving synagogue at the start of Passover, according to accounts first reported by Israeli media.

"Evasion of registration will result in citizenship revoke and you will be forced outside the country with a confiscation of property," read a translation of the flier.

The leaflet ordered Jewish residents to report to a government building occupied by pro-Russian forces as well as pay a fee.

"All citizens of Jewish nationality over age of 16, living on territories of Donetsk People's Republic, have to register with DPR commissioner of nationality before May 3rd, 2014 at the Donetsk Regional Administration, room 514, registration fee is $50," the leaflet read. "Must have in person $50 cash, passport, all available IDs, and documentation of ownership of real estate and transportation."

The pamphlets were stamped by the Donetsk People’s Republic and had the name of Russian separatist Denis Pushilin on them, but Pushilin claims he and his supporters had nothing to do with their creation and distribution.

Approximately 1.5 million Jews were executed by the Nazis and their collaborators in the territory of Ukraine during the Holocaust.

"This directly recalls Nazi tactics, like the registration of Jews and the confiscation of their property, and it strikes a very deep cord with everyone in the Jewish community," said Andrew Srulevitch, director of European affairs for the U.S.-based Anti-Defamation League.

"This is a politically manipulative use of anti-Semitism and the victims of this are the Jewish people because of the intimidation they feel as a result of it," he told FoxNews.com. "We condemn this anti-Semitism for its content, regardless of the source and motive behind it."

"The language obviously is alarmingly reminiscent of the language the Nazis used," added Sara Bloomfield, director of the United States Holocaust Museum in Washington, D.C. "It's very deliberately provocative and outrageous."

"Whoever wrote this knew this language would resonate deeply in a place where the Holocaust happened," Bloomfield said.

The report of the leaflets came as talks were under way in Geneva seeking to ease tensions in the Ukraine. The agreement reached was supposed to require pro-Russian militias in eastern Ukraine to give up their control of the government buildings they have seized in recent days. But Russian forces so far are refusing to budge until the Western-backed Ukrainian interim government resigns.

Elderly Jewish women could reportedly be seen crying as they were handed the pamphlets upon leaving synagogue on Tuesday.

Rosen said this is understandable.

"Growing up, I would see moments where something evoked a time during the Nazi era that my parents had to live through and you would see the strain on their faces," he said. "I can see how the elderly who lived through that period would suddenly have all the emotions come back from that time."