About 2:00 a.m.: Officers arrived at the hotel to assist with the man.
The man is now in police custody, facing charges of trespassing and unlawful carry, and as of mid-morning Sunday, reportedly waiting to sober up before investigators can continue with their questioning.
After detaining the man, Houston police found an AR-15, a shot gun, a handgun, and a boatload of ammunition. They also found other weapons in his pickup truck.
Houston police say an intoxicated and belligerent man at a downtown hotel where a New Year's Eve party is scheduled has been arrested for unlawfully carrying a weapon and trespassing after they found several guns and ammunition in his room.
The man, who had not yet been identified by police, was initially going to be arrested for disorderly conduct after he drunkenly refused to leave the hotel's bar, according to the Houston Chronicle.More news: Kabul Bombing Kills At Least 6; ISIS Claims Responsibility
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Police are waiting to interview the man until he has sobered up, Macintosh said.
Acevedo said on Twitter earlier Sunday that the situation was "contained" and there were no specific threats to Houston.
The hotel is planning a huge New Year's Eve party tonight, with celebrations across four floors and live music.
A police spokesman said Sunday afternoon that investigators couldn't speculate about the man's intent.