(CNN) -- In the wake of violent clashes in Charlottesville, Virginia, between white supremacists and counterprotesters, the Illinois State Senate wants white nationalist and neo-Nazi groups classified as terrorist organizations.
In a resolution authorized Sunday, lawmakers urge law enforcement to "pursue the criminal elements of these domestic terrorist organizations in the same manner and with the same fervor used to protect the United States from other manifestations of terrorism."
State Sen. Don Harmon, a Democrat who introduced the measure, said he did so in response to Saturday's "inexcusable violence committed by white nationalist & neo-Nazi groups in Charlottesville."
In a series of tweets, Harmon said it is "vital that we stand in total opposition to the hatred, bigotry & violence displayed by these groups."
Counterprotester run down by car
Hundreds of white nationalists and other right-wing groups converged Saturday on Charlottesville, which has drawn protests over the planned removal of a statue of Confederate Gen. Robert E. Lee.
Counterprotester Heather Heyer was killed when a car plowed into a crowd. The driver, James Alex Fields Jr., 20, has been charged with second-degree murder and state other crimes.
The Justice Department and the Federal Bureau of Investigation have launched a civil rights investigation into the deadly crash. Investigators will probe Fields' alleged motives and determine whether there's enough evidence to bring federal charges, perhaps under hate crime laws.
The FBI also investigates domestic terrorism -- and identifies suspects -- based on whether "goals are to achieve political or social change through activities that involve force or violence," according to federal guidelines.
But while Congress has formally defined "domestic terrorism," federal lawmakers have never created a crime to match the classification, CNN legal analyst Page Pate writes.
'Heirs to the Ku Klux Klan'
In calling for the protest organizations to be branded as terrorist groups, Harmon took to Twitter to slam them and their beliefs.
"They are the heirs to the Ku Klux Klan and the Nazis," he tweeted. "We fought two bloody wars in opposition to their ideologies. We must continue to fight those same twisted ideologies today."
"Diversity has always and will always make America stronger and better. We condemn these groups and their actions, as they are the opposite of what our country strives to be," Harmon tweeted.
The Illinois Senate planned to send copies of the resolution to President Donald Trump, members of Congress and Illinois Gov. Bruce Rauner.