A live evening news program on Russia's state television channel was interrupted by a person, now identified as Marina Ovsyannikova, who walked into the studio holding a poster protesting the war in Ukraine.
The moment was a risky protest in a country where independent media has been blocked or shuttered and it has become illegal to contradict the government's narrative of the war.
Here’s who the Russian journalist is and why she was arrested.
Who is Russian journalist Marina Ovsyannikova?
Ms Ovsyannikova graduated from the Russian Presidential Academy of National Economy and Public Administration (RANEPA) in 2005, and then attended the Kuban State University in Krasnodar, southern Russia.
Her Twitter has been deleted, with the site saying that the account no longer exists.
Before this happened, Ms Ovsyannikova wrote: “I don't know what will happen to me any time soon.
"My lawyer told me I might be facing time in jail from 5 to 10 years according to the criminal code.
“I don't regret it. I need your endorsement though. #StopTheWar”.
An independent human rights group that monitors political arrests Marina Ovsyannikova as the woman taking part in the Russian news protest on March 14th.
The group, OVD-Info, posted on its website that Ms Ovsyannikova, who identified herself as an employee of the station, was taken into police custody.
Speaking in a video address early on March 15th, Ukraine's President Volodymyr Zelensky has praised Ms Ovsyannikova for her actions.
What was the Russian news protest?
An anchor was speaking during the newscast when a woman appeared on camera behind her holding a sign with "no war" scrawled in English across the top, with a message in Russian below calling on people not to believe Russian propaganda.
Within seconds, the news program cut away to another scene.
Ms Ovsyannikova also spoke out against the war in a video on OVD-Info's website.
"What is going on now is a crime," she said. "Russia is an aggressor country and Vladimir Putin is solely responsible for that aggression."
Why was the Russian journalist arrested?
Russia's state TV regularly amplifies the government line that says troops entered Ukraine to save people from "neo-Nazis" and to defend Russians from a country that was preparing to attack. The invasion of Ukraine is being characterised in Russia as a "special military operation".
People in Russia have limited access to information from outside their country.
They have also launched a criminal case against her on the charge of spreading false information about Russian armed forces, her lawyer said on social media.
The case against Marina Ovsyannikova was launched under a law, enacted after the February 24 invasion of Ukraine, that penalises statements against the military, lawyer Dmitry Zakhvatov said.
If convicted, she faces up to 15 years in prison.
Mr Zakhvatov told the independent news site Meduza the case is likely linked to a protest Ms Ovsyannikova staged last month, holding a banner that said “(Russian President Vladimir) Putin is a killer, his soldiers are fascists”.
Additional reporting by PA.