An early morning house fire in Pauoa Monday caused an estimated $378,000 in damage to the structure and its contents, the Honolulu Fire Department said.

Two people died and third was seriously injured in the residential fire. The cause is still under investigation.

More than 40 firefighters responded to a two-alarm fire that broke out at the home on Booth Road just after 2:15 a.m. Monday. When they arrived, crews found the structure engulfed in flames, the fire department said.

A 77-year-old man managed to escape the blaze. Emergency Medical Services personnel treated him for burns to his right arm and legs. He was taken in serious condition to a hospital.

Two other people, a 77-year-old woman and 54-year-old man, were found dead in the home. Their names have yet to be released by the Honolulu Medical Examiner’s Office.

Fire crews extinguished the residential fire at 3:05 a.m.