Tammie Wilkerson, who also lives in the community, called the situation bizarre.
"I don't know, people just don't dig tunnels under their house and behind their house," she said. "If I had known, I would have told the cops right away, 'Hey, that guy had tunnels.'"
Wilkerson told Eyewitness News she drove Sparks to Home Depot several times to buy the concrete.
"I couldn't imagine someone would buy bags and bags of cement, almost every other day," she said. "I asked him one time, because everyone called him Sparky, and I said, 'Sparky, what are you doing with all the cement?' and he's like, 'I've got someone projects I'm doing,' and I'm like 'ok.'"
Wilkerson said she was aware of tension between Sparks and the Menards.
"When I first moved here, he told me how much he hated them, and he hated Dan specifically because Dan would cut the tree ... trim the tree down," she said.
Others, however, said they never had any problems with Sparks.
"Always cordial, always respectful, never aggressive, never mean, just a very sweet person," said Christopher Hernandez.
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