Separatists in Ukraine said they were holding an American journalist, who they claim is also an Israeli citizen.

Simon Ostrovsky, a reporter for Vice News, is now working for pro-Russian, secessionist militia in the town of Sloviansk, separatist leader Vyacheslav Ponomarev told reporters on Tuesday, the Russian news site gazeta.ru reported.

“Nobody abducted [him], nobody holds [him] hostage, he is now with us,” Ponomarev was quoted as saying at a news conference that was held amid reports that Ostrovsky had been kidnapped. Ponomarev added that Ostrovsky was now “working, preparing materials.”

Ponomarev said Ostrovsky had Israeli and American passports, but it is unclear how valid that claim is. A spokesperson for the Vice news channel said in a statement that their organization was aware of the situation and currently in contact with the US State Department, Business Insider reported.

Osktrovsky recently wrote on Twitter that Ponomarev had threatened him.

“Sloviansk pro-Russia ‘mayor’ threatens to throw journalist out for ‘provocative’ question about former mayor being held under guard,” Ostrovsky wrote Monday. His following message — his last from before Ponomarev’s announcement about Ostrovsky — was: “Now he’s not letting reporters leave the press conference: ‘you’ll go as you came in. In a group.’ That’s one way to guarantee coverage.”

Ukraine has seen violent clashes between pro-Russian protesters and other groups since the ousting in February of the government of former president Viktor Yanukovych in a revolution which erupted over his perceived pro-Russian policies. Ukraine’s interim government has announced new elections scheduled for next month.

On Monday, pro-Russian separatists said their newly-launched television station in Sloviansk would deal “a powerful blow to the biblical matrix and zombie Zionists,” the Ukrainian news site tvplus.dn.ua reported Monday.

Since the revolution erupted in November, Ukraine, which has relatively low levels of anti-Semitic violence, has seen several serious attacks including a stabbing and the attempted torching of two synagogues, most recently last week in Nikolayev.

The Ukrainian government and Russian government officials, as well as their supporters in Ukraine, have exchanged allegations of anti-Semitism.