For a harrowing couple of days, Facebook removed the page of the event that has gone viral in recent weeks. The event's creator, Matty Roberts, said that he had received a message from the social network saying the event broke its community standards. But the social network said that decision was an error on the company's part.
"This was a mistake and the event page is now available again," a Facebook spokesperson told Fox News.
Via Facebook, Roberts told Fox News that the page was "gone with no reason for about 2 days," as were two other "sister events," which he said were also deleted. Roberts added that after the media picked up the story, "the event was restored as if nothing happened."
Interest in the event has surged in recent weeks. More than 2 million Facebook users have now said they are going, up from slightly more than 400,000 two weeks ago and 1.5 million people as of July 17.
An additional 1.4 million people have said they are interested in attending the event.
Following the craze, British oddsmaker BookMaker.eu placed odds on the number of sign-ups for the event, with the over/under set at 2.3 million. The odds on the over were most recently at -160 and the under was at +130. That means a bettor who bet $100 would win back their original bet plus $130 if less than 2.3 million people attend.
BookMaker.eu also put odds on the number of arrests and whether aliens will actually be discovered. With regard to the number of arrests, based on what USA Today reports at the time of the event, the over/under is set at 9.5, with the under attracting most of the money, offering -350 odds.