Thirty-five Honolulu firefighters responded to a house fire in Lanikai Thursday afternoon, according to fire officials.
The two-alarm fire started just after 1:30 p.m. on Mokulua Drive.
When crews got to the scene, the house was fully engulfed in flames, according to fire officials.
All three occupants, two adults and a teenager, were not home at the time of the fire.
Emergency Medical Services officials said an 18-year-old woman, who tried to help put out the fire with a garden hose, was hospitalized in serious condition due to smoke inhalation.
"We just saw black smoke going crazy in the sky, and we could see just from three houses down -- flames rolling over the house," said witness Greg Ebbert. "It was intense. You could feel the heat."
Flames appeared to be extinguished at around 2:20 p.m.
The cause is under investigation.