United Flight had taken off late Saturday with some 250 passengers on board.

Highlights United Flight 179 was stuck for about 16 hours in Canada airport

Flight failed to take off due to -30 degrees Celsius temperature

Passengers forced to stay on board with no customs officers on duty

A medical emergency and a mechanical problem left passengers on a United Airlines flight stuck for about 16 hours on the frigid tarmac of a Canadian airport in the plane's barely heated interior, the CBC network reported.

United Flight 179 had taken off late Saturday from Newark, New Jersey en route to Hong Kong with about 250 passengers on board.

When a passenger suffered a medical problem the plane made an emergency landing at Goose Bay airport in Newfoundland and Labrador province, on Canada's east coast, the airline told CBC.

But after paramedics took him to hospital, the plane was unable to take off, reportedly because bitterly cold temperatures of -30 degrees Celsius (-22 degrees Fahrenheit) had caused a door to freeze.

With no customs officers on duty overnight, passengers were forced to stay on board, many shivering under the thin blankets handed out by flight attendants.

With food and water running short roughly 10 hours into the ordeal, officials finally arrived to deliver supplies from the Tim Hortons fast-food chain known in Canada for its coffee and doughnuts.

One of the passengers, Sonjay Dutt, reached by phone, said the plane was under-heated and that the arrival of the food and coffee was not enough to appease increasingly angry passengers.

Please help us. This is an emergency @united. People are not doing well. Running low on food. — SONJAY (@sonjaydutterson) January 20, 2019

A relief aircraft arrived in Goose Bay late Sunday morning. After the passengers were transferred to the plane by bus, it took off in mid-afternoon to take them back to Newark, where they originally came from the day before, CBC said.

Much of eastern Canada, as well as the US northeast, has been suffering through a glacial cold spell, with heavy snowfalls that have led to scores of flight cancellations.

At the end of the United ordeal, passenger Dutt tweeted that "it's been a long long long long day."