The 12 Uzbek nationals and one Kyrgyz citizen are awaiting extradition to Uzbekistan, where they are wanted in connection with the May 2005 unrest in the city of Andijon
The 13 are at a pretrial detention center in the central Russian city of Ivanovo, where they have been in custody since their arrest in June 2005.
Today's demonstration was organized by Grazhdanskoe Sodeistviye, a Moscow-based group that helps refugees in Russia.
Civic Assistance's Iraliya Galimulina, who coordinated today's protest, told RFE/RL from Moscow the 13 men could face torture if deported to Uzbekistan.
"The Uzbek [authorities] have fabricated the charges brought against them, and now the Russian prosecutor-general has decided to extradite them to Uzbekistan," she said. "It means they will be sent directly to prison, where they will be beaten until they confess that they are terrorists and confess to rising up against the authorities in Andijon. We're trying now to prevent their illegal extradition, which violates international legal norms."
Uzbekistan on August 9 said the 13 detainees are accused of funding and helping organize the Andijon uprising.
The Russian Prosecutor-General's Office announced its decision to extradite them on August 3, saying it had received assurances from its Uzbek counterpart that they will not be ill treated or executed.