A gas tanker truck exploded on a highway north of Mexico City on Tuesday, killing at least 22 people and injuring more than 30 as a fireball tore through cars and homes.

Pablo Bedolla, mayor of the Mexico City suburb of Ecatepec, said 22 people died in the blast that engulfed early morning traffic. Television footage showed burned-out vehicles and debris strewn all over the highway on the edge of the capital.

Local media reported that at least 10 of those killed were children.

"It was a ball of fire which exploded as though they'd put a spotlight in the whole window," resident Carlos Gonzalez Silva told Mexican radio. "We opened the door and it was like fire had blown through the whole of the garden."

Bedolla said the blast had injured more than 30 people and damaged 45. Emergency services in the State of Mexico, which abuts the capital, said 16 vehicles were hit by the explosion.

President Enrique Pena Nieto expressed his condolences.

Mexican radio station Formato 21 said a family of four, including two children aged 6 and 11, were among the dead.

In January, a massive blast at the headquarters of state oil giant Pemex in downtown Mexico City claimed dozens of lives.

Media reports said the gas tanker did not belong to Pemex. The state oil company said it would help in rescue efforts. – Reuters