AN out-of-control driver killed two little kids in front of their horrified mothers in New York on Monday — with one baby boy dragged about 30 metres down the road while still in his pram, authorities said.

The other child — the four-year-old daughter of Tony Award-winner Ruthie Ann Miles — was run over and killed, while her pregnant mother was also injured in the devastating wreck, sources said.

The driver reportedly ran a red light and hit and killed one-year-old Josh Lew and four-year-old Abigail Blumenstein.

Miles “was bleeding from her head. They had to cut her coat off”, bystander Leah Finnegan told the New York Post.

Miles’ daughter Abigail “was flat on her back, and when the ambulance came, they were giving her CPR”, added a witness, June Clark-Smith.

“I ran to the [mother], telling her, ‘Please, Miss, stay down.’ … She tried getting up on her knees and fell back down.’’

Miles — who won a Tony Award in 2015 for her role in The King and I on Broadway and also starred as Young-Hee in The Americans — was in a critical but stable condition in the intensive care unit at a New York hospital.

Miles was heading from a church event at a nearby community centre with friend Lauren Lew — who ran up to her dying child after the crash, knelt beside his body and frantically tried to revive him, a witness said.

“The mother was sitting there next to him screaming,’’ fourth-year medical student Andrew Macaluso, 26, told the New York Post. “She was just kind of, ‘Oh, God, this can’t be happening! Tell me this isn’t happening! What’s going on?’”

Police sources told the New York Post there is video surveillance footage from the scene, and it was unclear whether the driver had the light.

Dorothy Bruns, 44, reportedly told police she was trying to avoid hitting a car and swerved out of the way. She reportedly said she remembers waking up behind the wheel but was unaware that she had hit anyone. Police sources told the New York Post that Bruns would not be held in custody and was free to go.

Miles and Lew appear to be friends. In her acceptance speech for the Tony three years ago, she gave a shoutout to “the Lews”.

“I could fall and never hit the ground because of the amazing women who are my friends behind me,” she said.

Witness Jennifer Muñiz told the New York Daily News that the driver seemed unaffected by the deaths and injuries she had just caused, when paramedics removed her from the car.

“When they took her out she was just standing there, like nothing,” Muñiz told the New York Daily News. “No emotion. Not sad. Not crying. Not asking questions: ‘Is everybody all right?’ Not shaking. Nothing.

“She was texting on her phone like nothing happened. Like she had just parked the car.”

New York Mayor Bill de Blasio said a full investigation was underway regarding the tragic crash.

“For [my wife] Chirlane and I obviously this is very personal. It occurred in our neighbourhood, very, very close to our home,” de Blasio said.

“This loss of life is tragic and painful for all of us, particularly those of us who are parents.”