A Delta Air Lines flight out of Las Vegas was canceled Monday after several passengers and at least one crew member fell ill amid "uncomfortable temperatures" on the plane as they waited for it to take off during an unrelenting heat wave, the airline said.

Multiple customers on Flight 555, which had been bound for Atlanta from Harry Reid International Airport, were seen by first responders, including a passenger and a flight attendant who had to be transported to a local hospital, Delta said.

“We apologize for the experience our customers had on flight 555," the airline said in a statement. "Delta teams are looking into the circumstances that led to uncomfortable temperatures inside the cabin and we appreciate the efforts of our people and first responders at Harry Reid International.”

The airline said customers were accommodated on other flights and received direct apologies and compensatory gestures.

Video shared online by a social media user claiming to be on the plane showed someone being wheeled away on a stretcher.

Krista Garvin, a field producer for Fox News who said she was on the flight, called it an "INSANE experience." She said a number of passengers passed out because of the heat.

In a series of tweets, Garvin said that the flight was initially delayed and that once passengers were finally able to board, they were left sitting for "almost 3 hours on a hot plane in 111 degree weather" awaiting takeoff.

The plane ultimately had to head back to the gate because people were "passing out," she said.