New Year's guests at the 628-room Marriott were locked out of their rooms when the clock struck 12 and their electronic keys stopped working - for a staggering three hours.
Denver police say they were called to the hotel as fights broke out among frustrated guests.
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Locked out: New Year's guests at the 628-room Marriott in Denver sit outside of their rooms during the three-hour security glitch
Local KUSA-TV some revellers got sick in the hallways and the elevators were not working at the Denver Tech Center Marriott.
Denver police were called to the scene at 4900 South Syracuse Street but said no one was seriously hurt.
Crowds: Hotel guests swarmed the downstairs area, and brawls erupted among frustrated revellers
Inconvenience: Revellers got sick in the hallways and the elevators were not working at the Denver Tech Center Marriott, forcing guests to use the stairs
Scene: The 628-room Denver Tech Center Marriott was the only Marriott property that reported a lock-out
Police said a room key malfunction kept guests out of their rooms from midnight until about 3am.
The hotel’s general manager, Jennifer Atkins, says it wasn’t immediately known whether the malfunction was related to the year change.
Ms Atkins said she couldn’t confirm reports of fights and vomiting in the hallways.
She said there were no confirmed reports of key card problems at other Marriotts.
According to the hotel, rooms for all of the guests have been comped due to the inconvenience.
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