Two men were killed in an early morning house fire in unincorporated south King County on Friday morning.

Fire crews with Kent, Federal Way and south King County responded to a fully involved structure fire just after 4 a.m. at 3915 South 238th Street near Kent.

When crews arrived, they found flames visible from every window in the house. It took crews roughly 20 minutes to work on the fire.

Investigators said one of the men was found in the kitchen and the other was found in a front bedroom.

The men were described as 19 and 69 years old, and they are believed to be grandson and grandfather.

KIRO 7 reporter Alexandra Limon spoke with neighbors who tied to help the victims.

"I basically stayed on the other side of the wall until I heard him hit the floor. You know, I tried to stay with him. I heard him shuffling around from one room to the next," said neighbor Matt Irvin. "The most terrible part is feeling like you could have done something more."

Irvin helped by smashing several windows, but the fire was intense.

Minutes after, firefighters arrived and they had a difficult time too.

"I tried to fight their way into the house, but the smoke and the flames and heat were too much," said Don Barberie of the Kent Fire Department. 

Two adult female relatives got out of the house safe.

One neighbor, Mimi Wolfe, said that she saw the 19-year-old victim often during her morning walks.

"It's just said," said Wolfe. "I would see him come out of the house to go to school in the morning with his backpack on."

The Red Cross has arrived to assist the family. 

Two firefighters were also injured, but they were not seriously hurt. 

No other injuries were reported.