Honolulu firefighters responded to a two-alarm fire at a home in Kailua.

Nine units with 34 firefighters responded to the blaze that broke out at a two-story home on 1476 Kupau Street at 4:55 a.m. today.

When they arrived, they saw the second floor of the structure fully engulfed in flames, said HFD Capt. Scot Seguirant.

A neighbor alerted four occupants of the flames. Seguirant said they safely escaped the fire.

Firefighters had the blaze under control at 5:36 a.m. and extinguished it at 6:34 a.m.

Honolulu Emergency Medical Services personnel treated two neighbors, two women ages 76 and 93, for smoke inhalation. They refused to be taken to the hospital.

Motorists are advised to avoid Kupau Street and use alternate routes.

The cause of the fire and the estimated cost of damage has yet be determined.