As Russian media outlets say, police officers arrested about 300 people who participated in protest rallies supporting opposition politician Alexei Navalny.
The protest rallies were underway in approximately 40 Russian cities.
Reports say the law enforcers arrested them without any explanation.
Local media outlets say that about 60 cities are hosting the protest rallies.
Russian opposition politician Alexei Navalny was sentenced to 30-day detention.
On January 17, 2021, Russian law enforcers arrested Navalny when he arrived at Moscow Sheremetyevo International Airport.
Navalny was detained when his passport was being checked.
In August last year, during a flight from Omsk to Moscow, the Russian oppositionist became ill. The plane made an emergency landing, and Navalny was taken to the Omsk hospital's toxicology department. Then Navalny was transported for treatment to one of the Berlin hospitals.
In Berlin, a medical examination of Navalny established that the Novichok nerve agent had poisoned the Russian opposition leader.
This fact was regarded as an attempt on Navalny's life by the Kremlin. The Russian authorities have denied the accusation and said they had nothing to do with the incident.