Mexico ? A tanker truck hauling liquid petroleum collided with a freight train, killing at least two people, injuring at least 44 and reducing parts of a border-town settlement to rubble.

Witnesses said they heard two large explosions followed by a series of smaller ones Thursday, with gusts of fire ripping through cement-wall homes and blasting off corrugated metal roofing.

The truck, owned by Techno Gas of Monterrey, Mexico, was hauling two tanks of propane when it failed to stop after the train sounded a warning, witnesses said.

One tank exploded and the other seeped gas through a puncture, fueling flames that took Mexican and Texas firefighters hours to extinguish.

On Friday, authorities pulled the body of a 12-year-old boy from debris. A 17-year-old girl also died in the blast, but authorities said they did not know the fates of two other people – the driver and train engineer – who were originally reported killed in the blast.