Fire officials say the flames broke out at a home on Encina Street near Sequoia Avenue at about 4 am.
When firefighters arrived, they found the house up in flames in the city's historic district, where many buildings are more than 100 years old.
"They started an initial attack from the exterior, and then we sent a second crew inside the front door and attacked it from the interior. We did have one patient who has been transported to the hospital," said Visalia Fire Chief Dan Griswold.
That patient is a woman, who neighbors say was on fire as she ran out of the home and across the street for help.
She was first taken to Kaweah Health and is now being treated at Community Regional Medical Centers's Burn Center in Fresno.
Firefighters were able to contain the flames before anyone else was hurt, but the home sustained significant damage.
Woman hospitalized following house fire in Visalia, officials say
"Reports are that it's about 50% destroyed," said Griswold.
Firefighters were also concerned about an apartment complex next to the house, but they worked quickly to keep the flames from spreading.
"We didn't evacuate to any apartments. There was a large body of fire close to this apartment building, but we started putting water on that side to protect against exposure or we would call it.," said Griswold..
Visalia Fire says this was the 91st residential structure fire this year.
They are still looking into how it started.
Neighbors say there was also a cat in the home- which they believe didn't make it out.
We are waiting for word from firefighters on if they found any pets in or near the house.
The condition of the woman who was burned is unknown at this time.
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