Russian investigators on Wednesday launched the first criminal cases under a new law against spreading "false information" about Russia's military operation in Ukraine.
Signed by Russian President Vladimir Putin on March 4, the law introduced jail terms of up to 15 years for people who publish "knowingly false information" about the military.
It has alarmed his political opponents and independent media who see the law as a bid to further gag reporting on the military operation.
The first investigations target three individuals accused of posting "lies" on online messaging forums or social media, the criminal investigations committee said on its website.
The probes were based on information from the FSB secret service and the suspects' homes had been searched and restrictions placed on their movements, it added.
It identified one of the suspects as Veronika Belotserkovskaya, accused of sharing false information on Instagram.
"I have been officially declared an honest person," she said in reaction to Wednesday's announcement in a post to her 900,000 followers on Instagram.
The investigators said Belotserkovskaya was based overseas and they would be seeking an international warrant for her arrest.