Officers had entered the hotel early Wednesday in search of a man wanted on a felony warrant who was not found, but another man inside the room police threatened the officers and barricaded himself inside the room with three hostages, The Oklahoman reported Thursday.
Officers backed off and called a tactical team to the Clarion Hotel.
Officers attempted to negotiate with the man, identified as Clyde C. Boyette III.
Boyette, 47, released two women from the room unharmed during the daylong standoff.
The third hostage came out of the room about 10:50 p.m. and told police Boyette apparently had shot himself, police Master Sgt. Gary Knight said.
The hostage's name was not released by police.
Officials say they are investigating Boyette's death as a suicide.