Robert Corchado, 28, was named a suspect in connection with the crash that injured 15 at the day care on Goldenrod Road near University Boulevard. He may be trying to leave Orlando, authorities said.
Florida Highway Patrol troopers said they believe Corchado, the driver of a silver Dodge Durango, rear-ended a Toyota Solara, which crashed into the building.
The car wound up inside the front room and was removed around 6:45 p.m.
The driver of the Toyota wasn't injured.
Eight children were taken to Arnold Palmer Hospital.
One is in critical condition, three are in serious condition and one is in fair condition. Two children have been released.
Hospital officials said Quintus died at 6:45 p.m Wednesday.
In all, 13 people were taken to local hospitals from the scene.
Slideshow: Scene Images | SUV Damage
Raw Video: Medics help injured children | Car pulled from day care | SUV towed from house
News Conference: Update on person of interest | "We will find whoever is responsible"
Authorities located the Durango shortly after 5 p.m. in Winter Park. Witnesses said they saw someone drop it off at a house, get into another car and drive off.
Later Wednesday, authorities confirmed Corchado rented a small, black Mazda SUV from an Enterprise in Winter Park, with a Florida license plate CHR-Q41.
"It could have easily been his side of the school and he could have been one of them," said parent Yvette Santiago.
Santiago cried when she said she feared her 3-year-old son was among the injured.
"I’m glad he's fine, but it still breaks my heart knowing [that] there's a lot of other kids that got injured," she said.
One man said he saw the crash that led to the carnage inside the day care .
"I heard a crash, and I saw the black car run up over the sidewalk and into the school," said Jeezy Jenkins.
Skywitness 9 was over the scene as small children were carried out and put into stretchers and into ambulances.
An FHP trooper said there were a wide variety of injuries to the 12 children and two adults.
"The injuries on the children range from severe, critical and all the way though to minor," the trooper said.
Anyone with information is asked to contact authorities immediately.
Channel 9 has multiple reporters covering this story. Follow them all on Twitter: @TBarberWFTV, @DBroomWFTV, @KBelichWFTV and @CHeathWFTV.
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