Police detain a protester in downtown Moscow on May 26. | AP Photo State Dept. condemns crackdown on Russia protests

After Sen. Ben Sasse questioned why U.S. leaders were not commenting on the suppression of Russian protesters, the State Department criticized Russia's handling of peaceful protesters on Sunday, calling it "an affront to core democratic values."

"The United States strongly condemns the detention of hundreds of peaceful protesters throughout Russia on Sunday," said Mark Toner, acting spokesman for the State Department. "Detaining peaceful protesters, human rights observers, and journalists is an affront to core democratic values. We were troubled to hear of the arrest of opposition figure Alexei Navalny upon arrival at the demonstration, as well as the police raids on the anti-corruption organization he heads."


President Donald Trump and his White House have not commented on the situation, which came amid protests against corruption in the government of Russian President Vladimir Putin.

Toner said the United States will continue to monitor and "call on the government of Russia to immediately release all peaceful protesters."

"The Russian people, like people everywhere, deserve a government that supports an open marketplace of ideas, transparent and accountable governance, equal treatment under the law, and the ability to exercise their rights without fear of retribution," Toner said.

Sasse, who is a member of the Senate Armed Services Committee, released a statement earlier Sunday saying Putin's "thugocracy is on full display" and that U.S. leaders are expected to call out those who "trample the basic human rights."

"The United States government cannot be silent about Russia’s crackdown on peaceful protesters. Free speech is what we’re all about, and Americans expect our leaders to call out thugs who trample the basic human rights of speech, press, assembly, and protest," the Nebraska Republican said in the statement. Sasse opposed Trump during the 2016 elections and has frequently been critical of him.

Opposition rallies against the Russian government took place Sunday in more than 80 towns and cities across Russia. In Moscow, reports indicate more than 650 people have been detained, including Navalny, Putin's most-prominent critic in Russia. The protests spurred from allegations that Russian Prime Minister Dmitry Medvedev accepted more than $1 billion in bribes from state banks and wealthy businessmen.

Trump has come under criticism for his kind gestures toward Putin. The FBI also is investigating potential connections between Trump campaign aides and the Russian government, which US intelligence officials suspect tried to interfere in the 2016 elections to help Trump win.

Nahal Toosi contributed to this article.