A man was holed up inside the Westin Bonaventure Hotel & Suites on the 400 block of South Figueroa Street for several hours.
Authorities said the suspect claimed through the door that he had a gun in his room. He told officers he was high on marijuana and cocaine.
The suspect had been staying at the hotel for the last week, but the standoff started around 7:30 p.m. Wednesday.
The suspect was contacted by hotel security who notified him his credit card was not valid. When he was asked to leave, he became agitated and started making threats, according to Los Angeles police Capt. Todd Chamberlain.
Three floors of the hotel had to be evacuated. The guests on those floors were sent to other rooms.
Officials were able to enter the room and detain the suspect by putting tear gas in the air conditioning system.
Authorities said they aren't sure if the suspect really had a gun in his room. The incident remained under investigation.