A gas tanker truck exploded and burned multiple vehicles under a Mexico City highway, killing three people and injuring 70 others.

The crash of the truck carrying more than 49,500 litres of fuel on a major highway sent flames and smoke billowing over the south of the capital.

Mayor Clara Brugada called the explosion an emergency that burned nearly 30 vehicles and left 19 of those injured in grave condition, including the driver of the truck. Among those injured were a baby and a 2-year-old child.

Brugada said prosecutors were investigating, but it appeared that the truck exploded after it tipped over on the highway.

"This is a horrible accident," the mayor said at the site of the explosion.

The gas tanker laying on its side had the logo of the energy business Silza on its side.

Later

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