Some 300 masked pro-Russian militants wielding baseball bats on Monday attacked a branch of the bank owned by an oligarch regional governor who has voiced criticism of Moscow.
The gang attacked the Donetsk office of the powerful Private banking and metal industry holding belonging to Igor Kolomoisky, a billionaire who is also governor of the nearby region of Dnipropetrovsk.
They shouted slogans accusing Kolomoisky, 51, of being a "fascist" and "enemy of the people," an AFP reporter on the scene said.
A leader of Ukraine's Jewish community, Kolomoisky is worth $2.4 billion (1.7 billion euros).
Kolomoisky has been particularly vocal in his opposition to Russian President Vladimir Putin, attacking him as "not normal."
"He has gone mad with his mission to re-establish the Russian empire," he has said, vowing that "separatism will not pass in Dnipropetrovsk". Putin himself responded by calling Kolomoiski "garbage" and a "scoundrel".
The oligarch has hit the headlines recently in Ukraine by offering a bounty of $10,000 for each separatist held and handed over to the authorities.
The eastern Ukrainian region of Donetsk is in the grip of a separatist movement which the West believes is being backed by the Kremlin.
Second Anti-Semitic Attack in 24 Hours
This is the second anti-Semitic attack on a high-ranking Jewish official in Ukraine in 24 hours.
Earlier Monday, Gennady Kernes, the Jewish mayor of Kharkiv,was shot in the back by unidentified gunmen.
The rabbi of Kharkiv, Rabbi Moshe Moskowitz, told Arutz Sheva that the mayor is being operated on and that security forces are attempting to catch the shooters. The rabbi said the mayor had been jogging and was apparently shot in the back many times.
"This is a very dear Jew, with a warm and loving connection to the community, and we are shocked by the assassination,” said the rabbi. “We are praying for his health – Moshe son of Hana.”
The unrest in Ukraine has brought with it a rise in anti-Semitic attacks on the region's Jewish population, highlighted by such events as the stabbing of the Deputy Commander of ZAKA Kiev and Hatzalah Kiev Chairman Rabbi Hillel Cohen.