Russian riot police have beaten up the head of a prominent rights group and the leader of a liberal opposition party as they evicted the rights organization from its Moscow offices on Saturday, both men said.

In a dramatic raid that started Friday afternoon and lasted into the early hours of Saturday, dozens of men swept the offices of prominent rights group For Human Rights.

Several thousand people marched through Moscow on Wednesday to support detained or jailed anti-Kremlin protesters, a day after President Vladimir Putin accused Washington of supporting a protest movement against him.

Led by anti-corruption blogger Alexei Navalny, the protest dubbed the "March Against Butchers" was aimed at supporting twelve activists accused of violence at an opposition rally last year as well as jailed activists.

Russia's counter-terrorism agency said Thursday that special forces have arrested a man for planning a terrorist attack on Moscow that the agency had foiled last month.

The National Anti-Terrorism Committee said in a statement that troops from the Federal Security Service, or FSB, arrested Yulai Davletbayev in suburban Moscow Thursday morning.

Twelve Russians went on trial in Moscow on Thursday accused of violence at a rally on the eve of President Vladimir Putin's inauguration last year, in a process condemned by critics as a show trial aimed at suffocating dissent.

Ten defendants were participating in the hearing from inside a glass-walled cage known as an "aquarium" while two more, who are not under arrest, were seated on a bench.

Thousands of commuters were evacuated from the Moscow metro on Wednesday after a high-voltage electric cable caught fire, filling station platforms with smoke at the height of the rush hour, emergency officials said.

The emergencies ministry said around 4,500 people were evacuated after the fire broke out in a tunnel between the Okhotny Ryad and Biblioteka Imeni Lenina (Lenin Library) stations close to the Kremlin at around 8:20 am (0420 GMT).

Georgia on Tuesday lashed out at arch-foe Russia over the construction of a new barrier along its disputed frontline with the breakaway region of South Ossetia.

"The foreign ministry of Georgia expresses its deep concern over the installation of wire fences by the Russian occupation forces across the Tskhinvali region's occupation line," the ministry said in a statement.

A massive undersea earthquake Friday in Russia's Far East prompted a tsunami warning and unleashed tremors across Russia including in Moscow around 7,000 kilometers away, but caused no casualties or damage.

The U.S. Geological Survey (USGS) estimated the quake at 8.3 magnitude and placed its epicenter in the Sea of Okhotsk off the shore of the Kamchatka Peninsula at a depth of more than 600 kilometers (370 miles).

Moscow metro is set to auction off more than a hundred of its iconic blue carriages after updating its rolling stock, a spokesman told Agence France Presse on Thursday.

The 120 carriages will be sold in lots of three and the state-owned system hopes to raise a total of almost 8 million rubles ($255,221), said metro spokesman Alexei Manakov.

U.S. Secretary of State John Kerry met with Russian rights activists Wednesday as he faced a tough balancing act between trying to find common ground with the Kremlin on Syria and signaling support for the country's embattled civil society.

On his first visit to Russia as the top U.S. diplomat, Kerry conspicuously steered clear of criticizing Moscow in an apparent attempt to soothe months of tensions after President Vladimir Putin's return to the Kremlin for a new term last May.

At least 38 people died in a fire in a psychiatric hospital outside Moscow late Thursday night.

Police said the fire, which broke out at about 2 a.m. local time (6 p.m. Eastern, 2200 GMT) in the one-story hospital in the Ramenskoye settlement, was caused by a short circuit, the RIA Novosti reported on Friday.