A ground stop was issued Tuesday at Reagan National Airport near Washington, D.C., as passengers from a United Airlines flight were bussed to a terminal. 

When asked for comment, United Airlines referred Fox News to the FBI. 

“The FAA is aware of a reported security issue on an aircraft at Reagan Washington National Airport (DCA),” the Federal Aviation Administration wrote on X. “Passengers have been removed, and the aircraft is away from the terminal while authorities investigate.” 

“All flight operations are being held at Reagan National while passengers on a United Airlines flight are being offloaded and bussed to the terminal. We will provide more information as it becomes available,” added the Metropolitan Washington Airports Authority, which runs the airport. 

Emergency crews could be seen parked near the United Airlines airplane, according to WUSA9.

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

Fox News’ Grady Trimble and Ashley Cozzolino contributed to this report.