Two days later, Weedon and his wife were found shot to death, and their home had been burned to the ground.
Around town, suspicion immediately fell on Diekemper, an often belligerent and abrasive figure whose neighbors so distrusted him that they secretly called him "Sneak" because they were convinced he was always hiding something.
Diekemper, 60, is behind bars, awaiting trial on bankruptcy fraud charges, and has not been charged in the April 2007 slayings. State Police last week would not discuss any possible suspects and said there was not enough evidence to charge anyone. And Diekemper attorney Scott Rosenblum said his client had nothing to do with the killings.
But according to court papers filed this month, Weedon, a trucker on medical leave, had nervously told an FBI agent he feared Diekemper would burn down his home for going to the authorities. And Diekemper's neighbors near this town of 3,400 people 70 miles east of St. Louis said they feel safer with him behind bars.
"Everybody is worried he's going to get out," Diekemper's own brother, Wayne Diekemper, said from behind the wheel of his rusty, 1960s-model tractor. "We don't want him on the loose."
Joseph Diekemper -- "Joey" to those who know him well -- and his 64-year-old wife, Margaret, filed for bankruptcy in 2004, claiming assets of $1.7 million and liabilities of nearly $5 million. But bankruptcy officials suspected they weren't telling the truth. So did the bank managing their property.
In April 2007, the bank took out a large ad in the Carlyle Union Banner warning that anyone helping Diekemper hide his possessions could be breaking the law. The ad promised "CIVIL AMNESTY" to anyone who confessed.
It's not clear whether Weedon saw the ad or heard of it, or why he allegedly cooperated with Diekemper in the first place.
But Weedon, according to an FBI summary of the call, told an FBI agent he had stashed one of Diekemper's tractors behind a false wall Diekemper helped build in a shed on Weedon's land, tucked amid corn and soybean fields four miles off the highway.
The agent assured Weedon the FBI would be careful about disclosing his identity. Weedon agreed to call back the next week to arrange a formal interview.
But before he could arrange to come in, he was found dead in the front seat of a muscle car that he had been fixing up for someone else. Some 100 yards away, in the ruins of the Weedons' burned-out home, firefighters discovered the remains of Linda Weedon, a 41-year-old hospital worker.
In the days that followed, an investigator quietly told neighbors to watch their backs, and they heeded the warning.
Diekemper's 61-year-old brother slept with a high-powered rifle and packed a pistol in his bib overalls when on his tractor. Down the road, 62-year-old Ed Albat, shared a bed with a .40-caliber pistol and took it with him when he cut the grass.
Albat recalled that he once reported Diekemper to environmental regulators for dumping manure along the road, and Diekemper got even by spreading the waste so thick and so close to Albat's neighboring house that his four-wheel-drive machine got stuck.
"He did that just to spite me," Albat said. "Neighbors don't do that to other neighbors."
Wayne Diekemper said his brother was chronically in financial trouble.
"He always wanted to be the big cheese of the family," Wayne Diekemper said. "He wanted to outdo everybody, outfarm everybody. He was always bragging and carrying on."
Authorities said Diekemper -- an avid player of poker and blackjack, according to neighbors -- blew $115,000 in 190 trips to casinos.
Last summer, Diekemper and his wife were indicted on charges of defrauding their creditors and others by lying about -- and often hiding -- millions of dollars in real estate and farm equipment. Diekember has been jailed since July, when a federal judge revoked his bail after finding he had two rifles.
The Diekempers are scheduled for trial in December.
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