Turbulence was so bad on a United Airlines flight that five people were injured on Monday.

United Flight 1676 was heading to Billings, Montana  from Denver, Colorado on Monday when it hit extreme turbulence upon its landing. The turbulence lead to screaming and the descent was so dangerous that the pilot declared a medical emergency due to injuries, the Daily Mail reports.

According to the Federal Aviation Administration, the pilot "declared a medical emergency after a flight attendant was injured by turbulence. The plane landed in Billings without incident."

A spokeswoman for United Airlines said the airline is investigating and will do all that it can to prevent the incident from happening again.

"Our primary focus is assisting our employees and passengers who were injured, and our flight safety team will review what happened," the spokeswoman said according to the Daily Mail.

There were 114 passengers and five crew members on board the flight. Two of the passengers and three flight attendants had to be taken to the hospital. All were treated and released except for one flight attendant.

'There was a lot of screaming, a lot of hollering," passenger Bill Dahlin told KTVO. He said that the plane dropped suddenly, which stunned both the passengers and crew.

"I think they were somewhat panicked," said Dahlin. "I think they were trying to assess things themselves so they really didn't offer any explanation because of what happened so quickly."

Dahlin said that one female hit the ceiling of the plane, causing it to crack. Another woman was screaming out for her child as she had dropped it during the incident.

"I have flown a lot, and I do know you run into things like this" Dahlin said. "This [turbulence] happened to be a lot rougher than what I'm accustomed to."