Baby Sent Flying, 5 Hurt When Plane Hits Turbulence

Feb. 18, 2014— -- A baby was flung from its mother's arms and five people were sent to hospitals from injuries they suffered when a United Airlines flight hit severe turbulence over Montana, officials said today.

WATCH: Turbulence Hurts Passengers, Crew on United Airlines Flight

The turbulence happened as the Boeing 737 en route from Denver to Billings, Mont., was starting to descend before 1:30 p.m. Monday, causing a startling, sudden drop. Due to the situation, the flight's captain declared a medical emergency.

Bill Dahlin was a passenger on the flight. He spoke to ABC News about the chaotic scene.

"There was a gal in front of us. She went up, her head went through the roof, and there was a woman screaming for her baby," Dahlin said. "What really kind of grabbed your heart was the woman hollering for her baby. She was terrified."

Passenger Joe Frank told The Denver Post in an email that the baby was propelled into a nearby seat, but the infant didn't appear to be hurt.

"I didn't have my seat belt on, so I hit my head pretty hard, but what hurts is my lower back and hips," he said

The flight contained 114 passengers and five crew members.

Turbulence can happen at any time, even during clear weather conditions. An average of 32 people are injured nationwide each year due to flight turbulence, and more than two-thirds of the victims are crew members, according to the Federal Aviation Administration.

Dahlin said he's never experienced anything like it in his life.

"I'm all right with it, but I know there's other people that definitely had some issues," he said.

United Airlines released a statement saying the airline's flight safety team will review the incident.

ABC News' Dan Good, ABC News Radio and The Associated Press contributed to this report.