GRAFTON, MASS. (WHDH) - An elderly Grafton couple escaped injury Wednesday thanks to a passing AAA employee who alerted them to a massive fire that eventually reduced their home to a pile of ash.

Homeowner Norman Daigle and his wife had no idea what was happening until Norman Strom came rushing to the door.

“He saved our lives,” Daigle said. “He said ‘you got to get out of the house.'”

The four-alarm fire broke out around 1 p.m. on Milbury Street and raging flames quickly engulfed the home, despite the efforts of firefighters.

Video from Sky7 showed thick smoke billowing out of a structure on the property that housed an old welding shop. The fire spread to the home, rendering it a total loss.

Crews struggled to battle the flames because propane tanks exploded and ammunition detonated in the blaze, according to Grafton Fire Chief Michael Gauthier.

“We had a propane tank explode and missile through the air on us,” Gauthier said. “There was ammunition in the house because we heard some of it popping.”

Strom was driving by when he saw smoke coming from the garage. He alerted the Daigle’s, who were inside with their cat. He was able to escort them all to safety.

“I drove by to see smoke coming out of the garage,” Strom said. “By the time I got them out, the whole house was engulfed.”

Family members say they are beyond grateful to Strom for stopping and rushing in to help.

“I just want to say thank you Norman for everything,” the couple’s grandson Joshua Rane said. “It was so awesome what you did for my grandparents.”

The couple was taken to an area hospital as a precaution. Their home will need to be torn down.

The cause of the fire is under investigation.

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