Two United Airlines aircraft collided at San Francisco International Airport on Monday evening, according to reports. United Flight 1871, en route from San Francisco to Denver, was pushing back from its gate when it struck the tail of United Flight 796, which remained parked at its gate bound for Boston. No injuries were reported, and passengers from both flights deplaned without issue.

Video footage captured damage to the wing of one aircraft, while the parked plane sustained harm to its horizontal stabilizer. The departing aircraft, flight UA1871, showed damage near its auxiliary power unit. A failure in the towing bar of a tug was cited as the cause of the ground collision.

The incident occurred in an area where air traffic controllers do not communicate with aircraft, per the FAA. The agency has announced it will investigate the accident.