Police say a man who choked on his food while driving caused a chain reaction that led to a fireball exploding over a Walmart in southwestern New Mexico.

The Deming Headlight reports (http://bit.ly/YtpLbN) 61-year-old Robert Sheppard told police he was eating as he drove Saturday in front of the Walmart Superstore in Deming and that he began to choke, causing him to lose control of his pickup truck.

According to police, the pickup, traveling at a "high rate of speed," struck a propane tank attached to a grill.

Witnesses reported seeing a massive fireball that extended over the roof of the store.

Police say three people were injured in the crash.