Although the case was deemed a homicide, police have declined to list a cause, raising questions about whether Wheeler was drugged, shot, beaten, or stabbed. New information from police sources suggests he might have stopped taking medication for some sort of medical or mental-health condition.

"We're very disappointed that we've heard nothing," said Doug Thornblom, a retired Army colonel who described his roommate from West Point's Class of 1966 as a kind, respected, passionate patriot.

In a long, successful career, Wheeler fought for the Vietnam Veterans Memorial, advised high-level Washington officials on defense issues, worked as secretary of the Securities and Exchange Commission, and served as first chief executive of Mothers Against Drunk Driving.

"At a time when most of us are retired, he's not only employed, he's overemployed - and all in the service of his country," said Thornblom, who with other classmates, still close to Wheeler, expressed puzzlement and regret over the mystery of Wheeler's death.

He said Wheeler's work on issues ranging from cybersecurity to military tactics was fueling conspiracy theorists, and he suggested that investigators' reluctance to release their findings could make the case more difficult.

The often-wild conspiracy theorists, rife on the Internet, focus on Wheeler's employment at Mitre Corp., a prominent, government-funded defense firm. They suggest that his access to state secrets made him a potential whistle-blower on purported government cover-ups that include dead birds in Arkansas and Latin American espionage.

"The longer [police] remain silent, the more trash they're going to have to sort through," Thornblom said.

Randy Loftin, another classmate, said Wheeler's death shocked their tight-knit group.

"This is really off the charts for someone like Jack," Loftin said. "There are few people who would stun us like that, especially the way in which he died. He was a fabulous man, someone who was always watching your back in whatever you were doing."

Newark Police Lt. Mark A. Farrall, a spokesman for the department, declined to say whether detectives had more information and had chosen not to share it, or whether clues were scarce.

"Investigators are still working leads and conducting interviews," Farrall said. "Whether they are making progress, I just don't know."

The probe began at 9:56 a.m. Dec. 31, when Wilmington police were called to the Cherry Island landfill for a report of a body being dumped from a Waste Management Inc. refuse truck.

An official cause of death will not be released until "toxicology reports and other forensic studies" are completed, said Carl Kanefsky, spokesman for the medical examiner.

Farrall said investigators determined that the trash truck had made 10 pickups in Newark and that the location of Wheeler's body in the truck indicated it had been picked up early in the route.

Police said Wheeler had been scheduled to take an Amtrak train on Dec. 28 from his consulting job at Mitre, outside Washington, to the Wilmington stop. Farrall said police had not confirmed whether Wheeler was on the train.

"We just know he got back [to Wilmington]," Farrall said.

Classmates said they were stunned by a report from a law enforcement source that police had tied Wheeler to an arson attempt on the night of Dec. 28. Wheeler's strong opinions could rankle people at times, they said, but he was a stickler for obeying the law.

Wheeler had been embroiled in a four-year court battle with a neighbor over construction of a large house across from his own in a historic neighborhood. Police have said that smoke-bomb devices were set off in the unfinished house. They have not said officially that Wheeler was linked to the crime.

On Dec. 29, witnesses reported seeing Wheeler at a Wilmington parking garage, coatless and clutching one of his shoes. Video from the garage captured Wheeler wandering aimlessly, at times appearing agitated.

Wheeler told several people at the garage that he had been robbed but did not want them to call police. He said he was looking for his car. Police said it was parked a half-mile away in the garage across from the train station.

On Dec. 30, police said, surveillance video from the Nemours Building, about six blocks from the parking garage, showed Wheeler in different clothes but still looking "confused."

The West Point classmates, several of whom have watched the video, said they knew of no preexisting medical condition that might have contributed to Wheeler's impairment.