The Wall Street Journal said on Thursday that it "vehemently denies" the spying allegations brought by Russia's intelligence service against its reporter.

"The Wall Street Journal vehemently denies the allegations from the FSB and seeks the immediate release of our trusted and dedicated reporter, Evan Gershkovich," a spokesperson for the WSJ said in a statement to ABC News. "We stand in solidarity with Evan and his family."

The FSB said it detained Gershkovich in the city of Ekaterinburg, in central Russia, and accused him of collecting "state secrets" on an enterprise belonging to Russia's military industrial complex on behalf of the United States.

Russia's FSB intelligence agency said on Thursday it had detained a journalist working for The Wall Street Journal on spying charges.

Russian state media cited an FSB statement saying Evan Gershkovich was detained in Ekaterinburg, a city in central Russia, and accusing him of collecting "state secrets" on an enterprise belonging to Russia's military industrial complex on behalf of the United States.

A criminal case has been opened against him, the officials said.

"It is established that Evan Gershkovich, acting on the instruction of the American side, was collecting information consisting of state secrets, about the activity of one of the enterprises of the Russian military industrial complex. He was arrested in Ekaterinburg during an attempt to receive secret information," Russian media said, quoting FSB officials.

Earlier reports from local media said that Gershkovich had been in Ekaterinburg reporting on the Wagner private military company.

Gershkovich is a reporter for the WSJ covering Russia, Ukraine and the former Soviet Union. He previously reported for Agence France-Presse and The Moscow Times, according to his WSJ profile. He also served as a news assistant at The New York Times.

-ABC News Tanya Stukalova and Patrick Reevell

The U.S. will support the creation of a special tribunal to prosecute top Kremlin officials for Russia's aggression toward Ukraine, State Department officials said Tuesday, marking a significant shift for the Biden administration and a notable step toward outlining what accountability on the international stage might look like after the conflict.

A department spokesperson said the administration envisioned the tribunal would take the form of an international court that is "rooted in Ukraine's judicial system" but ideally located in another European country.

The spokesperson added that such a mechanism would work to "facilitate broader international support and demonstrate Ukraine's leadership in ensuring accountability for the crime of aggression" as well as "maximize the chances of achieving meaningful accountability for the crime of aggression."

Ukraine and other Western countries have long called for a special tribunal, but until now, the U.S. has not publicly declared if it would support the creation of a new structure.

-ABC News' Shannon K. Crawford

At least two people were killed and 29 were injured Monday morning when a pair of long-range Russian missiles slammed into buildings in a city in eastern Ukraine, Ukrainian officials said.

The two S-300 Russian missiles hit administrative and office buildings, and private homes in Sloviansk, according to Pavlo Kyrylenko, the regional governor.

Sloviansk is in the Donetsk region of eastern Ukraine, where heavy fighting has been waged since the start of the war.

The missiles struck the city around 10:30 a.m. local time, Kyrylenko said.

He said the town of Druzhkivka in the Donetsk region was also targeted in Monday's missile attacks. Kyrylenko said a Russian missile "almost completely destroyed" an orphanage in Druzhkivka, but there were no immediate reports of casualties.

"Another day that began with terrorism by the Russian Federation," Ukrainian President Volodymyr Zelenskyy said in a statement.

Zelenskyy said Ukraine "will not forgive the torturing of our people."

"All Russian terrorists will be defeated," Zelenskyy said. "Everyone involved in this aggression will be held to account."

ABC's Will Gretsky

Russia said Sunday that the U.S. has denied visas to Russian journalists who wanted to cover Foreign Minister Sergey Lavrov's trip to New York.

Lavrov promised that the decision will not be forgotten by their side.

"The country that calls itself the strongest, smartest, most free, fairest has chickened out, has done a silly thing and shown what its sworn assurances on protecting freedom of speech, access to information and so on are worth," he told reporters at the airport before his flight to New York.

"Most importantly, you can be sure: we will not forget, we will not forgive this," the minister told the pool of journalists who have not been granted U.S. visas.

The journalists had planned to cover Lavrov's appearance at the United Nations to mark Russia's chairmanship of the Security Council.

Russian Deputy Foreign Minister Sergei Ryabkov called the U.S.’s decision “outrageous” on Sunday, Interfax, a Russian news agency, reported.

There was no immediate comment from the U.S. State Department about the claim of refused visas, according to AP.

-ABC News’ Anastasia Bagaeva, Edward Szekeres, Natalia Shumskaia