Mares's story of a flaming mouse that scampered from a burning pile of leaves into his rural New Mexico home on Saturday drew media attention across the United States and the world.
Then on Monday, the 81-year-old told an Albuquerque television station that strong wind spread burning leaves, leveling his home of more than two decades.
But on Tuesday, Mares and his nephew stood by his original version that a mouse was the culprit.
"That dang mouse crawled in there," Mares said in a telephone interview from a motel in Fort Sumner, New Mexico, where he is staying with his nephew. "I have an awful hate for those critters."
In the interview, Mares recounted three times the series of events on Saturday: A little mouse got caught in one of the glue traps he'd set in and around his home.
"That dang mouse crawled in there"
victim of mouse arson
He was pleased - mice were a nuisance, they'd been bothering him for some time, leaving droppings everywhere. And they were hard to get rid of.
This mouse, too, was resilient - trapped but still moving. The glue was sticky; he couldn't pull the mouse off.
"There's no reason for him to lie about what he told us ... I don't doubt it at all"
Juan Chavez, Fort Sumner fire chief
So, according to Mares, he went outside and threw the whole package - mouse and trap - onto the burning leaves.
The mouse, now ablaze, scrambled to safety, then headed back for the house and disappeared inside a window.
About 90 seconds later, the house was on fire.
How did the mouse run away, still trapped in the glue?
"The fire melted the glue and he got away," Mares said.
Is that plausible? Juan Chavez, Fort Sumner fire chief said he thinks so.
"There's no reason for him to lie about what he told us," Chaves said. “I don't doubt it at all.”
Fire crews arrived within minutes of the blaze and questioned Mares.
"I think he knew right then what happened. It's the story he told us, it's the story he told everyone else," Chavez said.
Mouse 'took off'
Richard Mares, 37, who is helping his uncle recover from the fire and figure out what the future holds, said his uncle had told him the same story many times.
"He said the mouse wasn't dead and it took off," the younger Mares said.
"We're really devastated. We lost all photos of our family, all his papers. He's a veteran of World War II. He's been through a lot."
Could his uncle have been rattled by the events and mistaken about the mouse? "He may be a little confused," Mares conceded.
With no further investigation planned, Chavez said his department's report of the fire would reflect that the burning critter ran back to the house.