UPDATED 04/01/11 5:00 p.m.

DAYTON, Ohio (WBBM/CBS) — A plane headed for Chicago made an emergency landing in Dayton, Ohio, Friday morning, and at least two passengers were taken to the hospital.

A Federal Aviation Administration official says American Airlines flight 457 was headed from Reagan National Airport in Washington, D.C., to O’Hare International Airport.

LISTEN: Newsradio 780’s Nancy Harty reports

When the Boeing 737 reached an altitude of about 28,000 feet, two flight attendants said they were feeling dizzy, American Airlines said. The flight attendants recommended oxygen masks be deployed in the cabin, which they were. The plane had 132 passengers.

Meanwhile, the pilots looked for the nearest airport where they could make an emergency landing, and it turned out to be Dayton, the airline said.

Before the plane landed, four passengers fainted, but they were able to walk off the plane on their own after landing. Three of the passengers and one flight attendant were sent to a hospital in Dayton, but only for a general checkup, the airline said.

Passengers who later arrived at Chicago’s O’Hare Airport told reporters the first sign of trouble was when flight attendants were overheard asking for oxygen.  Miyoshi Landry said the plane dropped to 10,000 feet “so that everyone could breathe.”

Passengers said everyone remained calm and followed directions as best they could.

“All of us who have been on flights for 100 million years who hear (the demonstrations saying) ‘Do this, do that,’ went  ‘Oh my God, what do we do?’” Patricia McNally told CBS 2’s Roseanne Tellez.

Before the original takeoff at Reagan, passengers said the plane was held back so that maintenance crews could work on the jet’s air conditioning. They wonder if that was a factor in the events that followed.

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