A Mexican couple was killed and their daughter suffered serious injuries when their hot air balloon caught fire in the air and plunged to the ground in Mexico City.

The family, belonging to the city of Caujimalpa de Morelos, was on a joyride over the popular tourist area of the pre-Hispanic ruin site of Teotihuacan, northeast of Mexico City, on Saturday when the tragic incident took place, NYDaily reported. The victims were identified as Jose Nolasco, 50, his wife Viridiana Becerril, 38, and their daughter, Regina Itzan, whose exact age is not clear.

While the couple died in the fire, their daughter broke her arm when she reportedly jumped from the basket. She suffered second-degree burns and is expected to survive.

It remains unclear if there was a pilot on board the balloon.

A bystander captured the moment when the basket of the balloon caught flames. The video shows the basket burning for several seconds before the occupants appeared to either fall out or jump out of it.

"My God, people are falling," one onlooker said in Spanish, as per reports.

Watch the video here:

Mexican police launched an investigation into the cause behind the fire. Initial local reports suggest it could be linked to the fuel storage system.

Itzan's grandmother, Reyna Gloria Sarmiento, revealed that the family had gone for the ride on the occasion of her daughter's birthday. The couple also took a selfie right before their hot air balloon ride, NYPost reported.

"It was the birthday of my daughter Viridiana, Regina's mom, and they had prepared this ride as a surprise for her," Sarmiento said, as per the outlet. She added her granddaughter was in stable condition.

The Cuajimalpa Mayor's Office extended its condolences to the family and friends of Nolasco and Becerril. It also wished Itzan a speedy recovery.

"The Cuajimalpa Mayor's Office extends its condolences to family, friends and acquaintances of José Nolasco and Viridiana Becerril who died this morning due to the collapse of a hot air balloon in Teotihuacán," the mayor's office said in a statement on Facebook. "Our solidarity and prayers for Regina, wishing her a speedy recovery."

Located in the State of Mexico, San Juan Teotihuacán is popular for its twin Temples of the Sun and Moon, as per NBC News. It was a pre-Hispanic holy city that was one of the largest in the world at its apex between 100 B.C. and A.D. 750. However, it was abandoned after a massive fire, according to UNESCO.

GettyImages-668944088
Passengers were ejected from a hot air balloon after it crashed near Melbourne, Australia, Wednesday. Here, a hot air balloon flies in Martinborough, New Zealand, Apr. 16, 2017. Getty Images/Hagen Hopkins