An out-of-control SUV plowed into pedestrians at a busy Midtown intersection Friday, sending six people to the hospital, including a baby who was in critical condition with a head injury, officials said.

Police said the driver of a Chevy SUV somehow lost control at the intersection of Fifth Avenue and West 46th Street and hit pedestrians in the crosswalk, including an 11-month-old boy inside a stroller and his parents.

The vehicle proceeded to jump the curb and traveled onto the sidewalk in front of a Barnes and Noble bookstore, officials said.

"It came out of nowhere," said Ron Rivas, an Upper East Side resident who works in midtown.

"The stroller was destroyed -- I mean, it was completely shattered," he said.

Rivas and other witnesses said employees from inside the bookstore rushed out to help attend to the struck baby and other pedestrians as they waited for ambulances to arrive. Emergency responders were on the scene within minutes, according to witnesses.

The adults were taken to Bellevue Hospital with non-life threatening injuries and the baby was taken to New York Presbyterian Hospital in critical condition with a head injury, officials say. The infant's condition is said to be improving at the hospital.

"The way that car came careeing in, it's a miracle that no one died," said Rivas.

It's not clear what caused the driver to lose control, but investigators are looking into whether the rain played a role or if the driver hydroplaned. Police said no criminal charges will be filed in the accident.