KIEV, Jan. 12 – Thousands of protesters on Sunday urged Western powers to impose sanctions against Ukrainian officials a day after riot police used force against activists, leaving 10 seriously injured.

At least 50,000 opponents of President Viktor Yanukovych rallied in central Kiev on Sunday to call the U.S. and the European Union to impose the sanctions.

The massive rally was held in response to the violent crackdown late Friday and in early hours of Saturday. Yuriy Lutsenko, a former interior minister and one of the leaders of the protest, was in intensive care Saturday following the violent attack by police.

“We have the key appeal to our Western partners,” Arseniy Yatseniuk, the leader of the opposition Batkivshchyna party, told the rally. “It's time to act, time for words is over.”

“The first official who must be listed for the sanctions is Interior Minister Vitaliy Zakharchenko and the rest of their gang who give orders to beat the people,” Yatseniuk said. “This is the message we’re taking to the West.”

The U.S. Senate Committee on Foreign Relations is due to hold a hearing on Ukraine on January 15.

On January 7, the U.S. Senate passed a non-binding resolution urging the U.S. president and Congress to consider applying sanctions including visa bans and asset freezes against any officials who ordered or carried out violence against protesters.

Lutsenko's wife said Saturday he is in intensive care after riot police beat him several times in the head and he lost consciousness. She said her husband came to a demonstration in Kiev late Friday to persuade police not to use violence against pro-European Union demonstrators.

Ukrainian opposition leader Viktor Klitschko also said he asked European leaders to consider personal sanctions against government members.

The violence started after a Kiev court sentenced three men to six years in prison for a 2011 plot to blow up a statue of Soviet Union founder Vladimir Lenin.

Local news reports in Ukraine aired footage of badly beaten protestors, including Lutsenko. Opposition leaders say at least 11 protesters were taken to the hospital.

The Interior Ministry reported about 20 police officers had been injured in the clashes.

Anti-government protesters have filled the streets of Kiev and other Ukrainian cities since November, when Yanukovych reversed positions and refused to sign a trade deal with the European Union, opting instead for stronger ties with Russia.

Since then, Moscow has promised to buy $15 billion in Ukrainian debt and cut the price of Russian gas to Ukraine to strengthen the struggling economy.

The demonstrators are calling on the government to honor its promise to sign the deal with the EU. (tl/ez)