Two women were in serious condition Sunday after sustaining injuries in a two-alarm structure fire in Palolo.

The fire started about 10:40 a.m. on the upper floor of a two-story house at 3449 Paalea St. Firefighters extinguished the blaze before it spread to the bottom floor, but the lower floor sustained some water damage, firefighters said.

The cause was under investigation, but some suspected an electrical malfunction.

Three people were home at the time and got out before firefighters arrived. 

A 36-year-old woman was taken to the hospital in serious condition with slight burns to her leg, and a 52-year-old woman was taken to the hospital for smoke inhalation, paramedics said.

According to the Honolulu Fire Department, a total of 19 people who were renting the house were displaced.

A separate unit in the back of the structure was not damaged, the property owner said.