Federal authorities are investigating after a man with guns in his vehicle was arrested Saturday after he was stopped at a checkpoint near a campaign rally for former President Donald Trump.
The Justice Department said Sunday that the Secret Service and the FBI are investigating the incident in Coachella, California, about a quarter-mile from the rally venue.
"The U.S. Secret Service assesses that the incident did not impact protective operations and former President Trump was not in any danger," Martin Estrada, the U.S. attorney for Central California, said in a statement. "While no federal arrest has been made at this time, the investigation is ongoing."
A federal law enforcement official said there is no indication that there was an attempt to assassinate Trump.
Get top local stories in San Diego delivered to you every morning. Sign up for NBC San Diego's News Headlines newsletter.
Riverside County Sheriff Chad Bianco said at a news conference Sunday that the man in question was stopped around 5 p.m. local time Saturday at a checkpoint to enter the "inside perimeter" of security protecting the venue, where all vehicles were to be stopped, when a deputy noticed his SUV was disheveled inside and displayed "an obviously fake license plate."
Deputies found two unregistered firearms — a shotgun and a loaded handgun — and "multiple boxes of ammunition," Bianco said.
The venue is a ranch used for competition and practice by the Empire Polo Club, which gave its previous home venue, in adjacent Indio, to concert promoters behind the noted Coachella Valley Music & Arts Festival.
The man who was stopped, identified as Vem Miller, said he was invited to the rally by another attendee and, at the same time, was permitted to attend as a journalist, Bianco said. Deputies found multiple fake identification cards, including passports, under different names in the SUV.
Miller, 49, of the Las Vegas area, was booked on suspicion of carrying a loaded firearm and possession of a large-capacity magazine of the type outlawed in California, according to Riverside County inmate records. Both are misdemeanors.
He was released before midnight, the records indicate. Bianco said further investigation about why he was trying to get to the venue on false pretenses is the purview of federal law enforcement.
A Secret Service official said in a statement: "We were contacted as it happened and Secret Service agents conducted a productive intelligence interview. It had no impact on the event and we are looking into the circumstances and the backgrounds of the individuals."
An official familiar with the situation said Trump was not at the venue when the man was stopped.
Asked about the arrest, a Trump campaign official appeared unaware of the incident. When additional information was provided, there was no comment or response.
Trump, running as the Republican nominee for a second presidential term against Vice President Kamala Harris, was the subject of assassination attempts in July and September.
On July 13, a gunman hit Trump in the ear and fatally shot a man at a campaign rally in Butler, Pennsylvania. The gunman was killed. And on Sept. 15 at Trump International Golf Club in West Palm Beach, Florida, not far from his home, a man suspected of being a would-be gunman was discovered hiding in bushes.
Bianco said the man who was stopped Saturday made it through an outer perimeter after "he gave all indications that he belonged there." But he expressed confidence that the man did not have much chance of getting beyond the inner perimeter, especially with a story that included having gotten permission to attend from a third party, which he said was not realistic.
"You don't get to give away passes to a rally for a former president," said Bianco, who has declared his political support for Trump.
He said the entry process also included getting past metal detectors at a Secret Service pedestrian checkpoint at the entrance.
Bianco said the situation could have been much worse if fast-acting deputies had not stopped the man early in the process to enter the rally.
“I was completely confident that there was absolutely nothing going to happen inside that facility,” he said.
Bianco cited the allegedly fake license plate and what he described as the vehicle's lack of paperwork, including registration, as indications the man may be affiliated with the anti-government sovereign citizens movement.
Miller was scheduled to appear in court on the weapons violations case in nearby Indio on Jan. 2.
Kelly O'Donnell, Jake Traylor, Andrew Blankstein and Tom Winter contributed.
This article first appeared on NBCNews.com. Read more from NBC News here: