A top Republican senator called out President Trump on Twitter Saturday, after Mr. Trump declined to condemn white nationalists when violence at a "Unite the Right" rally in Charlottesville, Virginia left one person dead and 34 others injured.

Sen. Cory Gardner (R-Colorado), leader of the National Republican Senatorial Committee in 2018, called on Mr. Trump to "call evil by its name." Mr. Trump, in brief remarks Saturday from his working vacation at his golf club in New Jersey, said he condemned violence "on many sides." Given a chance to clarify what Mr. Trump meant by "all sides," a White House official told the press pool the president was "condemning hatred, bigotry and violence from all sources and all sides. There was violence between protesters and counter protesters today."

But that wasn't good enough for Gardner, who had perhaps the strongest statements of any Republican Saturday afternoon.

Mr. President - we must call evil by its name. These were white supremacists and this was domestic terrorism. https://t.co/PaPNiPPAoW — Cory Gardner (@SenCoryGardner) August 12, 2017

At least five other Republican senators agreed with Gardner's language. Sen. Ted Cruz (R-Texas) tweeted he wanted the Department of Justice to investigate the incident.

I urge the Department of Justice to immediately investigate and prosecute today's grotesque act of domestic terrorism. — Ted Cruz (@tedcruz) August 13, 2017

Sen. John McCain, meanwhile, referred to the white nationalists as "traitors."

White supremacists aren't patriots, they're traitors- Americans must unite against hatred & bigotry #Charlottesville https://t.co/Zr1Jg9jBXu — John McCain (@SenJohnMcCain) August 12, 2017

Sen. Marco Rubio (R-Florida), also had strong words for the president.

Very important for the nation to hear @potus describe events in #Charlottesville for what they are, a terror attack by #whitesupremacists — Marco Rubio (@marcorubio) August 12, 2017

Sen. Orrin Hatch (R-Utah) didn't call on the president specifically, but as someone who lived through World War II and lost a brother to that fight for freedom, said, "we should call evil by its name."

We should call evil by its name. My brother didn't give his life fighting Hitler for Nazi ideas to go unchallenged here at home. -OGH — Senator Hatch Office (@senorrinhatch) August 12, 2017

The one death reported so far in Charlottesville resulted when a car plowed through a sea of counter-protesters, leaving one person dead and 19 injured. The protests began as a response to the removal of a statute of confederate General Robert E. Lee from a public park.

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Mr. Trump, in his remarks, said bigotry and hatred has gone on for a long time. He declined to answer a reporter's question as to what he would say to white nationalists who say they support him.

"We're closely following the terrible events unfolding in Charlottesville, Virginia," Mr. Trump said. "We condemn in the strongest possible terms this egregious display of hatred, bigotry and violence, on many sides."

We must remember this truth: No matter our color, creed, religion or political party, we are ALL AMERICANS FIRST. pic.twitter.com/FesMiQSKKn — Donald J. Trump (@realDonaldTrump) August 12, 2017

Political observers on Twitter compared Mr. Trump's reluctance to name any groups in Charlottesville to his criticism of former President Barack Obama for failing to use terms like, "radical Islamic terrorism."