A military unit of United States of America posted a tweet on September 20 that said it would use Stealth bombers against anyone who would try to trespass into restricted area in Neva. unit later took down tweet and apologized for same on September 21. 

A threatening tweet?

deleted tweet posted on September 20 on twitter handle of DVIDS(Defense Visual Information Distribution Service), targetted people who were fans of UFO's  and curious people flooded desert surrounding Area 51 this particular week after someone started an online petition to raid discreet military base that has long been a subject to rumours about housing secrets on aliens and UFOs.

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Also, tweet h men and women in ir military uniform in front of stealth bomber that US military possesses. Here is a screenshot:

response to 'joke' was less than welcoming: 

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Storm Area 51

raid that took place on September 20 at Area 51 which is also a US Air Force base that comes within Neva test and training range, h witnessed more than 2 million people ing on 'going' button and more than a million people ing interested button in a Facebook event created by Matty Roberts on June 27. Matty ded that she would t be responsible for any consequences as event that she created was purely based on entertainment purposes. 

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Humourless tweets

American Air Force last year h apologized for a tweet that was aimed at finding a funny response in relation to killing of Taliban militants in Afghanistan. Also, US strategic command responsible for America's nuclear weapons h tweeted that y were on rey to use 'something bigger' than iconic New Year's Eve Ball which drops in New York. 

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