Medical personnel were on hand to check out 175 passengers complaining of feeling ill aboard a United Airlines flight, after an issue with cabin pressure forced the flight to turn around and make an emergency landing.

An airline spokeswoman tells CNN that the Chicago to Denver flight took off at 9:01 a.m. this morning, but soon after hitting 15,000 feet, descending below 10,000 feet where unpressurized planes can safely fly.

“The flight landed safely, and we requested paramedics meet the flight to assist a few customers who reported feeling ill,” said the spokeswoman. “Maintenance is inspecting the aircraft as we accommodate the customers.”

The plane was met by seven ambulances so medical personnel could check out the 175 passengers who complained of ear pain or nausea, but no passengers or crew were taken to the hospital.

The Federal Aviation Administration is also investigating why the plane had to make the emergency landing.

Medics check 175 aboard United flight after emergency landing [CNN]

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