All passengers onboard American Airlines flight 564 are safe and sound after a "mechanical error" forced the aircraft to make an emergency landing at Los Angeles International Airport (LAX) Thursday morning, confirmed an American Airlines spokesperson.

"The aircraft, an Airbus A319 with 125 passengers and a crew of five, landed safely and taxied to the gate," reported the airline, saying it had been "diverted to Los Angeles due to a mechanical issue."

The Airbus A319 model aircraft departed San Jose, Calif., around 9:50 a.m. for Phoenix Sky Harbor International Airport, according to ABC News.

However, a few minutes into the flight, eight people, including a flight attendant, reported experiencing breathing problems from an unspecified odor aboard the aircraft. The passengers' oxygen masks were deployed and the pilot declared an emergency, contacting flight support for permission to land.

The local fire department was called to monitor the landing due to the nature of the emergency and were standing nearby - as requested - when the plane landed at LAX at 10:59 a.m., according to Los Alamitos-Seal Beach Patch.

Firefighters then examined the eight people who reported "minor respiratory irritation." All of them declined further treatment, including one woman who asked to be transported to a hospital before changing her mind, according to the Associated Press.

It's unclear what the source of the mystery odor was. An official said that a maintenance team was called to evaluate the aircraft to determine the root of the problem, noting that despite some of the passengers complaining of an odor, no one actually saw any smoke.