More than three million people had expressed an interest in attending a planned Area 51 event (Picture: Zuma Press/PA).
The United States military has apologised for a tweet posted ahead of a planned 'Storm Area 51' event.
On Friday, the Defense Visual Information Distribution Service (DVIDS) Twitter account posted a photo of US personnel standing in front of a B-2 stealth bomber, stating it was "the last thing #Millenials will see if they attempt the #area51raid".
The tweet has since been deleted and an apology issued via the DVIDS Twitter account.
"Last night a DVIDSHUB employee posted a Tweet that in NO WAY supports the stance of the Department of Defense. It was inappropriate and we apologize for this mistake," the subsequent tweet said.
The now-deleted tweet came as there were fears thousands of people could 'Storm Area 51' in the Nevada desert.
This ultimately failed to materialise, despite more than 1.5 million people saying they were going to an event on Facebook called 'Storm Area 51, They Can't Stop All of Us'.
In total five people were arrested on the remote once-secret military base, a Lincoln County Sheriff has confirmed.
Nearby 'Alienstock' and 'Area 51 Basecamp' festivals were held in the tiny desert towns of Rachel and Hiko.
On Friday at 3am, almost 100 people went to the best-known 'back gate' of the legendary former top-secret US Air Force base, near the tiny town of Rachel, and another 40 made a more difficult trek to a lesser-known gate in Tikaboo Valley.
About 300 went to the Tikaboo gate during daylight, and another 800 people made the dusty eight-mile drive to the Rachel gate during the day.
Two men were arrested after military security officers found them in the mountains inside the perimeter of the base somewhere between the two gates.
Authorities were trying to determine how to tow their vehicle out of the rugged area.
The gates are marked by bright floodlights, watchful cameras and, at the Rachel gate, a bunker building with blackout windows - all surrounded by razor wire.
Matty Roberts, a 20-year-old from Bakersfield, California, sparked the Area 51 phenomenon with a late-night Facebook post in June.
Area 51, referred to by the US government as Nevada Test and Training Range, is a top-secret military facility as part of the Edwards Air Force Base.