Two Southern California men are accused by federal authorities in an alleged plot to attack a Ultimate Fighting Championship event over the weekend at the White House, according to court documents.

In a post on X Tuesday, FBI Director Kash Patel said the agency foiled an attack and multiple people were taken into custody. Federal court documents show the plan, which authorities said was discussed online by several people, included using drones with explosives to hit buildings near the UFC Freedom 250 fight and have snipers target “certain high value targets.”

“On June 10, FBI and our law enforcement partners became aware of a potential threat to the UFC America 250 event in Washington, D.C. involving individuals outside of the National Capital Region — and thanks to the rapid action of this FBI, our partners, and the Department of Justice in a multi-state operation, multiple individuals are now in custody and allegedly planned attacks were stopped cold,” Patel said in the post.

In a federal complaint, two Southern California men identified as Bryan Omar Roa and Michael Alan Thomas — along with others — are accused of plotting to kill government officials and other people at the Ultimate Fight Championship on the White House lawn. President Trump and other high-level officials were in attendance. Trump, attending Group of Seven summit in France, said he was not briefed on the attack investigation.

The FBI said Roa’s seized cellphone contained “communications with co-conspirators about the attack plan.”

UFC fighter Josh Hokit sparked backlash after making a comment about Michelle Obama during a post-fight interview at UFC Freedom 250 on the White House lawn.

Roa said he attempted to drive to Washington, D.C. to protest the UFC fight, but denied involvement in the alleged plot, the FBI said. He told the FBI his vehicle malfunctioned before making it to the nation’s capital, according to court documents.

Thomas spoke with law enforcement and said he saw himself as a planner and advisor, but was not willing to participate in any attacks, according to the criminal complaint.

Messages exchanged by Roa and Thomas indicated they discussed living in Southern California and met at least once to practice marksmanship and tactics related to violent anti-government ideology, according to court documents.

The Inland Empire men made their initial appearances in U.S. District Court in Riverside on Monday. A federal magistrate judge ordered them to remain in custody without bond.

Roa’s arraignment is scheduled for July 7. Thomas’s arraignment is scheduled for July 21.

A senior law enforcement official told NBC News that the plot was “quite serious.”

Among other people arrested was a 19-year-old man in Ohio, where the alleged plot was discovered, according to court documents. Tycen Proper was charged with attempted murder and several firearms violations after telling investigators he helped plan an attack, according to an affidavit filed in the case.

Details about a motive for the attack were not immediately available.

The UFC event in front of the White House included a heavy law enforcement public safety presence and came after a series of acts of political violence. Nearby streets were blocked off and fences were set up to control crowds.

Reached for comment, an FBI spokesperson referred NBC News to Patel’s post. The Justice Department declined to comment, and the White House did not immediately provide comment.

In a statement on X, Secret Service Director Sean Curran said that his agency “worked closely with the FBI throughout this investigation.”

“In the days leading up to this weekend, our special agents, mission support personnel, and technical security teams worked around the clock to identify those responsible and hold them accountable,” Curran wrote. “Equally important to our protective mission is ensuring accountability through the justice system.”