A former U.S. Navy SEAL has been convicted over a thwarted plan to use explosives against law enforcement officers during a “No Kings” protest in California, a case federal investigators traced back to a warning from a store clerk.
Gregory Vandenberg, 49, was found guilty following a five-day federal trial on charges of transportation of explosives with intent to kill, injure or intimidate, and attempted transportation of prohibited fireworks into California, the U.S. Attorney’s Office for the District of New Mexico said.
The jury reached its verdict after deliberating for roughly three hours.
According to prosecutors, Vandenberg was traveling from El Paso, Texas, to San Diego ahead of the June 14, 2025, demonstrations when he stopped at a travel center near Lordsburg, New Mexico, and bought six mortar-style fireworks along with 72 M-150 firecrackers.
Surveillance footage shows Gregory Vandenberg talking with a store employee as he purchased fireworks in New Mexico. Employees later alerted law enforcement after he allegedly spoke about attacking officers at California’s No Kings protests, federal authorities said. (United States Attorney’s Office for the District of New Mexico)
During the transaction, federal authorities said, Vandenberg told a clerk that he planned to throw the explosives at law enforcement officers during the protests.
Prosecutors said he asked multiple times about how much gunpowder the fireworks contained, whether taping several mortars together would make them more powerful, and stated that his interest was limited to their ability to injure officers.
Gregory Vandenberg is seen wearing a shirt that reads “AMALEK” while buying fireworks at a New Mexico travel center on June 12, 2025. (United States Attorney’s Office for the District of New Mexico)
Vandenberg also encouraged the clerk to attend the protests and hand out fireworks to others, telling the employee he would not get hurt because of his military experience, according to trial testimony.
The conversation alarmed employees enough that they wrote down Vandenberg’s license plate and contacted law enforcement before he reached California.
Federal agents tracked Vandenberg to Davis-Monthan Air Force Base in Tucson, Arizona, where he was arrested the following morning while sleeping inside his vehicle.
Prosecutors said he falsely claimed he was traveling for work despite being unemployed and later told investigators he was visiting friends in Phoenix.
A search of Vandenberg’s vehicle uncovered the fireworks along with clothing displaying antisemitic, anti-Israel and extremist imagery, according to prosecutors.
Among the items recovered were shirts bearing an Al-Qaeda flag, a shirt calling for the destruction of Judea, a hat featuring the Al-Qaeda flag and apparel displaying a variation of the Black Sun, a symbol associated with neo-Nazi ideology.
Federal prosecutors said investigators recovered an Al-Qaeda flag hat from Gregory Vandenberg’s vehicle after his arrest en route to California’s No Kings protests. (United States Attorney’s Office for the District of New Mexico)
Jurors were also shown photographs of Vandenberg wearing a custom-made T-shirt bearing the word “AMALEK” while inside the travel center. Prosecutors said Vandenberg told investigators the word meant “destroyer of Jews.”
Investigators also discovered Vandenberg’s cellphone home screen displayed a Taliban flag. A forensic review of the phone uncovered what prosecutors described as violent extremist content, including antisemitic, anti-Israel and anti-U.S. material, as well as messages discussing the upcoming protests.
Federal investigators recovered clothing bearing extremist and antisemitic imagery from Gregory Vandenberg’s vehicle, according to court records. (United States Attorney’s Office for the District of New Mexico)
According to prosecutors, those messages suggested Vandenberg believed the U.S. government, including President Donald Trump, was controlled by Israel and Jewish people, evidence they argued helped establish his motive for targeting law enforcement officers.
“People in this country are free to hold their own beliefs and to express them peacefully,” Acting U.S. Attorney Ryan Ellison said in a statement. “What they are not free to do is use explosives to threaten or terrorize others.”
Ellison added that Vandenberg “intended to turn explosives into a tool of intimidation,” and said the verdict “sends the message that attempts to substitute violence for expressing one’s opinion has no place in our communities and will be met with federal consequences.”
Vandenberg was later sentenced to 16 months in federal prison, where he remains in custody. Upon his release, he will serve one year of supervised release.
