Russian opposition activist Alexei Navalny was detained after a visit to the dentist on Wednesday, he said on Twitter.
In the tweet, he said authorities had detained him and were taking him somewhere after he received treatment for a toothache. The reason for his arrest was not immediately clear. He did not say where he was detained, but the activist lives in Moscow.
Navalny is the best-known political opponent of President Vladimir Putin. He has been banned from taking part in the country’s March 18 presidential election because he carries a fraud conviction, which he has dismissed as a groundless and politically motivated move to keep him off the ballot.
Navalny has been arrested several times, including in January, when he led anti-Kremlin protests calling for a boycott of the elections.
He rose to prominence by posting investigative stories online about the alleged corrupt practices of Russia’s elite.