Half a million people have signed up to “storm” a US military base that conspiracy theorists say holds alien technology.
The event is called Storm Area 51: They Can’t Stop All Of Us and says: “We will all meet up at the Area 51 Alien Center tourist attraction and coordinate our entry.
“If we naruto run, we can move faster than their bullets. Let’s see them aliens.”
Naruto run is the unique running style of Naruto Uzumaki, the star of the Japanese anime series Naruto who sprints with his arms stretched behind him.
The event, set for 20 September, is likely a joke. Its creator is best-known for posting memes and streaming content on Twitch, a live streaming platform for gamers, according to comicbook.com.
According to US media, the Air Force is aware of the Facebook post but is not commenting further.
Area 51 is about 150 miles from Las Vegas, it is not open to the public and is under 24-hour surveillance.
The remote 4,000-square-mile patch of desert was first used for the development of U2 spy planes in the 1950s.
That programme finished after the U2 was put into service around 1956 and the base has since been used for testing other military aircraft.
But conspiracy theorists say the site has also been used to store remains of crashed UFOs and other alien technology.
The US government’s official line is that what happens at Area 51 is classified for the purpose of national security.
But that and the fact that they only acknowledged the base’s existence in 2013 has only fuelled the speculation.
Peter Merlin, a US aerospace historian who has written extensively about Area 51, told NBC News that the facility is “strictly a place for testing and evaluating aircraft and associated weapons systems”.
He also said that anyone who shows up on 20 September may find themselves more at risk from the unforgiving desert terrain rather than the bullets of those who guard the facility.
“The security guards could just sit back and wait,” he said. “They don’t have to do anything if they don’t want to. The desert will take care of these people.”