Marina Ovsyannikova, who works for Channel One, was arrested soon after.
An employee of a state-owned Russian news channel interrupted a live broadcast to protest Russia's invasion of Ukraine.
Waving a sign that said "Don't believe the propaganda" while shouting "stop the war", Marina Ovsyannikova interrupted the night broadcast of Channel One on Monday. The channel then switched its broadcast from the studio to recorded footage.
She was arrested soon after and taken to a police station.
According to the Guardian, Ovsyannikova is an editor at Channel One. She also released a pre-recorded video where she said, "Regrettably, for a number of years, I worked on Channel One and worked on Kremlin propaganda, I am very ashamed of this right now. Ashamed that I was allowed to tell lies from the television screen..."
The Guardian quoted her as urging other Russians to "go to the protests" as "only we have the power to stop all this madness".
According to Reuters, Ukraine president Volodymyr Zelenskiy thanked Ovsyannikova in a video address, saying, "I am grateful to those Russians who do not stop trying to convey the truth. To those who fight disinformation and tell the truth, real facts to their friends and loved ones. And personally to the woman who entered the studio of Channel One with a poster against the war."