Transcript for Passengers stranded on Canadian runway for over 18 hours

Back now with the passengers stranded on a runway in Canada, for more than 12 hours. Cold, hungry, and miserable. What happened on this united flight? Here's Maggie Rulli. Reporter: Tonight, passengers reliving what they call an utter disaster. This is the worst experience I've ever had. Reporter: For nearly 19 hours, sonjay Dutt says he was trapped on this united airlines flight from New Jersey to Hong Kong. The plane diverting to Canada due to a medical emergency, then getting stuck, after mechanical problems caused by the minus-25 degree temperatures. They weren't sure what was going on. They weren't sure where they were going to take us. They weren't sure if they were going to take us to Newark or on the west coast. Reporter: Passengers say even the crew grew frustrated by the different reasons given for the delay. The pilot was so sick of being looked at as a guy that's lying to the passengers, he flat-out said, "Look, here's the CEO's e-mail, e-mail him." Reporter: All 250-plus passengers are trapped inside. United telling them they couldn't leave because of an issue with customs. And tonight, those passengers air finally on their way. But in the wrong direction, landing back at Newark, demanding answers and wanting their money back. This definitely needs to be handled better. Reporter: Tonight, united is apologizing to their customers and says its crew is doing everything possible to help the passengers. Maggie, thank you. When we come back, brand new

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