UFO enthusiasts have been descending on rural Nevada near the secret US military installation known as Area 51, long rumoured to house government secrets about alien life.
Some residents of Rachel, a remote desert town of 50 people a short distance from the military base, worried their community might be overwhelmed by unruly crowds turning out in response to a recent, viral social-media invitation.
Dozens of visitors began arriving outside Rachel's only business - an extraterrestrial-themed motel and restaurant called the Little A'Le'Inn - parking themselves in cars, tents and campers.
Area 51 was shrouded in secrecy for decades, stoking conspiracy theories that it housed the remnants of a flying saucer and the bodies of an alien crew from the crash of an unidentified flying object in Roswell, New Mexico, in 1947.
The US government did not confirm the base existed until 2013, when it released CIA archives saying the site was used to test top-secret spy planes.
In June, California college student Matty Roberts posted a facetious Facebook invitation exhorting the public at large to go to Area 51 to "see them aliens."
When more than 1 million people expressed interest, the US Air Force admonished curiosity seekers not to breach the gates at the military base, which it said is still used to test combat aircraft and train personnel.
Roberts teamed up with the Little A'Le'Inn to plan a music festival in Rachel dubbed "Alienstock" to entertain the expected crowds.
He's since disassociated himself from the event, saying he feared it could devolve into a public safety crisis.
The Little A'Le'Inn's co-owner Connie West said the event in Rachel would go on as planned.
"It's happening. There was no stopping it," she said, adding that some visitors had come from as far away as Australia and New Zealand. "I hope they just enjoy the party we are throwing."
Australian Associated Press