Passengers were evacuated from a plane at Denver International Airport Sunday after one of the engines caught fire. The United Express jet operated by SkyWest was bound to Denver from Aspen and had landed when the fire started, according to authorities.

Photos from the scene showed flames coming out of the left engine and on the ground. Fifty-nine passengers were evacuated safely and nobody was injured, Marissa Snow, a spokesperson for SkyWest told NBC News Monday. Four crew members also evacuated and were unharmed.

“The passengers were actually taken on a bus back to the concourse,” said airport spokesperson Heath Montgomery, according to KDVR-TV. “Part of what we do is we assist the airlines in getting the passengers back to a safe place.”

First responders were called to put out the flames. Videos and images posted to social media showed foam being used to extinguish the fire.

“They very quickly reacted,” said Montgomery. “They extinguished what they found to be a fire in the rear section of the aircraft.”

At least one passenger took to social media to praise the handling of the incident.

“Quick and immediate response,” a passenger wrote on Twitter. “First responders on runway. Huge thanks to pilot and crew for helping get passengers off safe.”

The National Transportation Safety Board was notified of the incident, according to airport officials.

Engine fires aren’t wholly uncommon on planes — while the United Express flight caught fire after it landed, a United Airlines plane caught fire in June after it took off when a bird struck the engine. The bird forced pilots to shut down the flight bound from Chicago to Miami after flames ignited while the plane was in the air.

At least one passenger tweeted a video of the flames coming out of one of the engines while the plane was still in the air. The pilot landed the plane back at Chicago’s O’Hare International Airport less than an hour after it took off. One witness said he was driving near the airport and saw flames spewing out of the plane.

“I was just driving and I couldn’t focus my vision on it, so I couldn’t identify it,” Marco Vargas told WBBM Newsradio at the time. “It was a long flame shooting out of the right engine. I called 911.”

Once a fire is detected onboard an aircraft, a crew has only about 17 minutes to get the plane back on the ground, according to the Flight Safety Foundation and Aer Lingus.

“Without aggressive intervention by the flight crew, a fire on board an aircraft can lead to the catastrophic loss of that aircraft within a very short space of time,” the organization said. “Once a fire has become established, it is unlikely that the crew will be able to extinguish it.”