The FBI foiled an alleged plot to attack Sunday’s UFC fight at the White House, FBI Director Kash Patel said in a post on X.

“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.

The FBI director shared a story from Fox News, which reported that a group allegedly planned to use drones with explosives to hit buildings near the fight and target the crowds as they fled with a sniper team. Fox News also reported that other alleged perpetrators then planned to storm the White House gate. NBC News has not confirmed the details of the alleged plot.

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

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

This is a developing story. Please check back for updates.