The onetime aide to Presidents Ronald Reagan, George H.W. Bush and George W. Bush was found dead on Dec. 31 in a Wilmington, Del., landfill. Police have ruled his death a homicide but have yet to locate the crime scene or find a weapon.

Incendiary devices were found at the home of the neighbor with whom Wheeler had been entangled in a property dispute at the time of his death and a law enforcement source said investigators believe Wheeler may have set them, the Philadelphia Inquirer reported.

Wheeler, an Army veteran who played a key role in the creation of the Vietnam Veterans Memorial in Washington, also went to a New Castle pharmacy last Wednesday and had an unusual request, according to a report.

“He said, ‘Can you give me a ride to Wilmington?’ and that was a flag,” a pharmacist told the News Journal. “He looked like he was a little upset.”

Less than an hour after leaving the drug store, Wheeler was at the New Castle County Courthouse parking garage in Wilmington, searching for his car “erratically,” employees at the garage said.

One worker said that Wheeler was carrying his right shoe in his left hand and claimed someone had stolen his briefcase. His car was later found a few blocks away at another parking garage where authorities say Wheeler was a monthly customer.

The defense contractor was last seen on Thursday, Dec. 30, in downtown Wilmington, two blocks from the office of the lawyer who was representing him in the real estate dispute.