The influx began at 3 am local time, reports the AP. Two people have been detained, one of them for urinating in public places. No attempt to storm the base has yet to be reported.

Already on Thursday evening several hundred people camped in the nearby desert town of Rachel, where the band Wily Savage played at an outdoor concert after dark, while the temperature dropped to 7 plus degrees.

A joke on the internet

The call to storm Area 51 on September 20 was published jokingly, but since then two million people have accepted the event on Facebook. Although only a fraction of them appear at the military base in the Nevada desert, it is enough to worry the authorities.

The military has warned that those who try to get into the base are at risk of being shot. The police, for their part, have said that the area outside the base is a public place and that everyone can get to the entrances, but that those who go further will be arrested.

Two Dutch youtubers were recently sentenced to one year in prison for attempting to enter the prohibited area, but the sentence was converted to three days in jail and fined.

Lincoln County authorities are prepared to handle up to 30,000 visitors, says local rescue officer Eric Holt. Hotels, souvenir shops and campsites have also been equipped for the storm.