Marina Ovsyannikova detained days after she demonstrated near the Kremlin holding placard criticising Putin and Ukraine war

Russian police detained and later released the journalist Marina Ovsyannikova, who in March interrupted a live television broadcast to denounce the military action in Ukraine, posts on her social media channels showed.

Her detention on Sunday came a few days after 44-year-old Ovsyannikova demonstrated alone near the Kremlin holding a placard criticising Russia’s intervention in Ukraine and president Vladimir Putin.

“Marina has been detained,” her entourage said in a message posted on the journalist’s Telegram account. “There is no information on where she is.”

The message included three photos of her being led by two police officers to a white van, after apparently having been stopped while cycling.

Shortly after, Ovsyannikova posted images of herself and two dogs on her Facebook page.

“Went for a walk with the dogs, just stepped outside the gate, people in uniform approached me,” she wrote. “Now I’m sitting in Krasnoselsky ministry of internal affairs,” referring to a police station in a Moscow district.

Three hours later, Ovsyannikova said she had been released. “I’m home. Everything is okay,” she wrote on her Facebook page. “But now I know it’s always best to bring a suitcase and passport if you go out.”

Her lawyer, Dmitri Zakhvatov, earlier confirmed her arrest to the Ria-Novosti news agency, saying: “I assume that it is linked one way or another to her act of protest.”

In March, Ovsyannikova, an editor at Channel One television, barged on to the set of its flagship Vremya (Time) evening news programme holding a poster reading “No war” in English.

On Friday, Ovsyannikova posted photos of herself on Telegram showing her near the Kremlin and carrying a protest placard raising the deaths of children and denouncing Putin as a “killer”.

Declarations of this kind expose her to criminal prosecution for publishing “false information” about and “denigrating” the army – offences that can carry heavy prison sentences.

Ovsyannikova became internationally famous overnight in March when she staged her live TV protest. Pictures of her interrupting the broadcast went around the world.

She was briefly detained and then released with a fine, but while a number of international observers praised her protest, it was not universally acclaimed by Russia’s opposition.

Some critics said she had spent years working for a channel, Pervy Kanal, that they said was effectively a mouthpiece for the Kremlin.

In the months following her March protest, Ovsyannikova spent some time abroad, including a brief period working for the German newspaper Die Welt.

In early July, she announced that she was returning to Russia to settle a dispute over the custody of her children.