Sound checks echoed from a distant main stage while Daniel Martinez whirled and danced at dusty makeshift festival grounds just after sunset in Rachel, the Nevada town closest to the once-secret Area 51 military base.

For sociologist and pop culture expert, event that was born without pretensions on Facebook risks becoming a security crisis in a protected area of the U.S. government.

Authorities admit they don't know what to expect as the 'Storm Area 51, They Can't Stop All of Us' event kicks off in rural Nevada.

About 75 people arrived early Friday at a gate at the once-secret Area 51 military base in Nevada - at the time appointed by an internet hoaxster to "storm" the facility to see space aliens - and at least two were detained by sheriff's deputies.

The music kicked off weekend events — inspired by an internet hoax to “see them aliens” — that Lincoln County Sheriff Kerry Lee said had drawn perhaps 1,500 people to two tiny desert towns.

When an event that invited people to take the "Area 51" to see the aliens received more than 2 million "I'll be there", its creator Matty Roberts revealed that everything was a joke and canceled that event. However, it was too late and people are motivated to attend.

The Air Force has issued stern warnings for people not to try to enter the Nevada Test and Training Range, where Area 51 is located.

Alien seekers have begun to gather in southern Nevada, with two people detained on September 20 near the entrance of Area 51, a military base surrounded by myths of extraterrestrial visitors.

Crowds coming to desert for hoax-turned-festival worry locals, and the Air Force

Residents prepare for influx of people near restricted US military site after online joke received millions of responses

Visitors descending on the remote Nevada desert for “Storm Area 51” are from Earth, not outer space.

One local residents predicts that the people who show up to raid the military facility won’t “find what they’re looking for, and they are going to get angry.”