The Jacksonville Sheriff's Office has arrested Gregory William Loel Timm, 27, on two counts of aggravated assault on a person older than 65 and one count each of criminal mischief and driving with a suspended license.
No one was hurt in the incident.
In a string of social media posts, the Duval County GOP - which sponsored the registration drive - said six of its volunteers were "intentionally targeted" at about 2:45 p.m. when the van "accelerated" toward them.
"We are outraged by this senseless act of violence toward our great volunteers," Duval GOP Chairman Dean Black said in a statement. "The Republican Party of Duval County will not be intimidated by these cowards and we will not be silenced."
The group shared photos of an overturned tent, a toppled table and Trump 2020 campaign signs strewn around the parking lot. Officials said Republican volunteers plan to "redouble" their efforts to register voters and continue to fight "with renewed intensity to re-elect President Donald Trump."
As word spread and Republican Party leaders and elected officials weighed in, Trump issued a warning on Twitter.
"Be careful tough guys who you play with!" he wrote alongside a statement from GOP Chairwoman Ronna McDaniel. She called the incident an "unprovoked, senseless" attack and said "these disgusting acts will only make us work harder to win in November."
Among those who condemned the attack were Sen. Rick Scott, R-Fla., a former governor of the state; Sen. Marco Rubio, R-Fla.; and Rep. Steve Scalise, R-La., who was shot and seriously wounded in 2017 while practicing with other Republican lawmakers for the annual Congressional Baseball Game.
"There's no place for violence in politics. We settle differences at the ballot box," Scalise said in a tweet after the Duval County incident. "This can't be the new normal. Democrats need to join me in condemning this behavior."
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