The car Wheeler was driving was found to have been stolen from Pinellas Park, Fla., when the tags were routinely checked by a trooper in Frederick County at 5:30 p.m.
An attempt to stop him launched the 50-mile chase through two counties at speeds reaching 100 mph, police said.
Amazingly, only one motorist was run off the road during the chase which involved dozens of sheriff's deputies and troopers from two counties and ended when Wheeler lost control just before 6 p.m. and plowed into the median just east of Md. 615, police said.
The motorist wasn't injured and damage to the vehicle was light, police said.
Traffic was stopped in both directions and police began what turned out to be eight hours of negotiations to get Wheeler out of the car.
Wheeler's brother from Butler, Pa., was brought to the scene in an unsuccessful attempt to talk him out of the car, police said. A special hostage team was also summoned to the scene.
During the eight hours, Wheeler stayed in the vehicle, periodically waving the gun toward police negotiators and then pointing the gun to his head and threatening suicide, police said.
Wheeler was drinking beer throughout the incident and as time passed, he became more aggressive, police said.
At 2 a.m., Wheeler was warned that tear gas was going to be shot into his car, police said. As the tear gas was fired, Wheeler put the gun to his head again and shot himself, police said.
A medic unit from Hancock Ambulance Company was on the scene and provided immediate medical attention but Wheeler was later pronounced dead.
Police said they believed the man was on the way to his home state of Pennsylvania.
"Wheeler was wanted in Florida for a parole retake,'' Bachtell said this morning. He was also wanted on outstanding warrants in Pennsylvania for burglary and in Maryland for a burglary in Berlin, Md., Bachtell said.
The car was a 1991 Oldsmobile 98. Heavy damage to the right front of the car was visible as the vehicle was towed into the state police barracks this morning.
Wheeler's body was held at the barracks until it was picked up this morning for transport to the medical examiner's office in Baltimore for autopsy, Bachtell said.
The standoff produced another headache for police as traffic continued to back up in both directions through the night and police tried to detour it onto U.S. 40 around the scene.
"We were getting a lot of calls from motorists in their cars telling us they were running out of fuel," Sgt. Tom Woodward said. "We were concerned about that, plus the cold temperature out there."
Some motorists were able to turn into Hancock to take other routes, witnesses said.
"We could see traffic trying to come through here to find better routes," said Tonya Strait, shift manager of Pizza Hut in Hancock.
At the Hancock Truck Stop, business was brisk.
"We've had lots of people coming in to get something to eat," said Tamara Wilson, truck stop cashier. "They can't get around the roadblock, so they're stopping in here."
Staff Writer Brendan Kirby also contributed to this story.