A Russian court on Tuesday convicted four journalists of extremism for working for an anti-corruption group founded by the late opposition leader Alexei Navalny and sentenced them to 5 1/2 years in prison each.

Antonina Favorskaya, Kostantin Gabov, Sergey Karelin and Artyom Kriger were found guilty of involvement with a group that had been labeled as extremist. All four had maintained their innocence, arguing they were being prosecuted for doing their jobs as journalists.

Russian-American woman Ksenia Karelina, who was serving a 12-year prison sentence for treason in Russia, was released as part of a prisoner exchange that saw her swapped for an accused smuggler held in the US.

US Secretary of State Marco Rubio said on X early on Thursday that Karelina had been released and was on her way to the United States.

“American Ksenia Karelina is on a plane back home to the United States. She was wrongfully detained by Russia for over a year and President Trump secured her release,” Rubio said on X.

Russia and the U.S. carried out a prisoner swap early Thursday in Abu Dhabi in a sign of continuing confidence building, as the two sides pursue a deal to end the war in Ukraine.

Russian-American ballerina Ksenia Karelina was released from Kremlin custody in a prisoner swap with the United States Thursday morning.

Karelina was freed in exchange for German-Russian Arthur Petrov at a swap in Abu Dhabi, the Wall Street Journal reported.

“American Ksenia Karelina is on a plane back home to the United States,” Secretary of State Marco Rubio said.

“She was wrongfully detained by Russia for over a year and President Trump secured her release. @POTUS will continue to work for the release of ALL Americans,” he added.

Russia and the United States have started talks on joint rare earth metals and other projects in Russia, and some companies have already expressed an interest in them, President Vladimir Putin's investment envoy said in remarks published on Monday.

Amid efforts by U.S. President Donald Trump to end the war in Ukraine, minerals cooperation has been floated by both Kyiv and Moscow, though Trump said on Sunday that Ukrainian President Volodymyr Zelenskiy wants to back out of a proposed deal.

Donald Trump has said he is "very angry" and "pissed off" with Russian President Vladimir Putin after weeks of attempting to negotiate a ceasefire in Ukraine.

In an NBC News interview, the US president criticised Putin for attacking Ukrainian President Volodymyr Zelensky's credibility, and threatened to impose a 50% tariff on countries buying Russian oil if he did not agree to a ceasefire.

Last week, Putin suggested the possibility of a UN-run government in Ukraine to organise new elections and then begin peace talks.

The State Department was allegedly warned about Lee Harvey Oswald's plan to assassinate John F Kennedy months before the president was killed, a new trove of top secret files about the assassination has revealed.

In a never before seen letter, which was released Tuesday evening with thousands of other unredacted documents, a man named Sergyj Czornonoh told the US British Ambassador how he warned authorities about Oswald's murder plot multiple times.