Out of the two million people who said they were going to “Storm Area 51” on September 20 and finally “see them aliens.”, it’s safe to say that most people RSVP’d as a lark, taking part in a viral Facebook joke with a click of a button.

Two YouTubers, though, really made the trip, reportedly traveling from the Netherlands to Nevada to visit the site and were arrested for trespassing.

Police officers were called to the Nevada National Security Site — a government nuclear facility 10 miles from Area 51 — on Tuesday after two men were spotted inside the perimeter, the Nye County Sheriff’s Office said in a video statement. After arriving at the military site, the police found a parked car belonging to the pair three miles inside the perimeter. Inside the car was a laptop, a drone, and a camera that upon inspection revealed footage shot inside the facility. The two men, later identified by deputies as Ties Granzier, 20, and Govert Charles Wilhelmus Jacob Sweep, 21, were subsequently arrested on trespassing charges. Business Insider reports that both men are YouTubers from the Netherlands.

Police said that Granzier and Sweep told them that they “speak, write, and read” English and saw the “No Trespassing” signs at the government facility, but decided to ignore the warning, because they wanted to see the facility, which is near Area 51, the military site long believed to be a secret alien holding site.

Matty Roberts, the man who started the Area 51 Facebook group said he thinks the event he started as a joke has gotten out of hand and this may be more evidence of that.

The U.S. Air Force has issued a warning about the so-called Area 51 raid, saying that “any attempt to illegally access military installations or military training areas is dangerous.”

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