A Southwest Airlines plane flying from Denver, Colorado, to Dallas, Texas, underwent a maintenance review after it made an emergency landing Saturday following depressurization of the cabin.

Southwest flight 861 was flying with 120 passengers when the cabin of the flight started to lose pressure at 20,000 feet in the air. Around 9 p.m. local time (10 p.m. EDT), oxygen masks were deployed as the plane neared the Dallas Fort Worth International Airport.

"The Crew of Flight 861 traveling from Denver to Dallas Saturday night radioed ahead for paramedics to meet the aircraft after a pressurization issue in flight," the representative of Southwest Airlines told Business Insider. "Following an uneventful landing, initial reports indicate four of the 120 Customers onboard requested a check from paramedics to assess ear pain. All of the Customers were ending their journey with us in Dallas, as was the aircraft, which underwent a maintenance review."

However, in a separate statement to CBS News, the airline said: “The pressurization event was related to an aircraft duct that resulted in the oxygen masks deploying; the cabin did not depressurize.”

A number of the passengers onboard the aircraft at the time took issue with the fact they were not given enough information by the flight crew regarding the emergency situation as it developed at the time.

Passenger Glen Eichelberger said that after the oxygen masks dropped down, the flight attendants told the people to put them on as the cabin was losing pressure.

"I had no idea what was going on or what the outcome was going to be," said Eichelberger. "I reached over and grabbed Josh [his friend and co-passenger) by the arm because I didn't know if we were going to make it or not. There was no communication whatsoever from the flight attendants or from the cockpit as far whether we were in mortal danger."

"When you're in the air 20,000 feet above the ground and don't know what's going on, it's not uneventful," he said, taking issue with the phrase used by the airline in its statement to Business Insider.

Passenger Josh Trimberger, on the other hand, said they got lucky with the timing of the incident. “Luckily, we were in the DFW area where we have Alliance, Love Field and DFW,” said Trimberger.

However, he did acknowledge that such mishaps can happen regardless of the precautionary measures. “They do thousands of flights a day and it’s a rare instance that this happened and I think it could have happened to anybody,” said Trimberger.

The two of them said the horrific experience would not stop them from flying on Southwest in the future but they hoped customer safety will be a priority for the airlines.

Southwest Airlines made headlines last month when a passenger was killed during an emergency landing. In the incident, one of the flight engines exploded and a shrapnel gouged a hole in one side of the plane, causing the cabin to depressurize and the woman to be sucked toward the opening.

Southwest Airlines
A Southwest Airlines plane flying from Denver, Colorado, to Dallas, Texas, was undergoing maintenance review after it made an emergency landing Saturday, following a depressurization of the cabin. In this photo, a Southwest Airlines jet sits on the runway at Philadelphia International Airport after it was forced to land with an engine failure, in Pennsylvania, April 17, 2018. Getty Images/ DOMINICK REUTER