Heavy police activity around the Cromwell hotel-casino.
The Drai's BeachClub & Nightclub, which is on the top floor of the building, was also evacuated.
The man's actions caused quite the commotion and led to some sporadic fights breaking out.
Additional police officers from other area commands responded to help with crowd control, maintain order and ensure the safety of those in attendance.
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Travel lanes on Las Vegas Boulevard in front of the hotel were blocked as police responded to the situation.
Two misdemeanor arrests were reported.
A night earlier, Rivera says more than 2,000 people were evacuated from the Cromwell after a report of gunshots that officials later attributed to the sound of velvet rope stands being knocked to a tile floor. According to reports from the scene, the loud noises had resulted from a brawl in the vicinity of the casino entrance, which had toppled a number of ornamental statues.
However, despite the initial panic, it later transpired that no shots had been fired.