The call to Mama Mia's pizzeria came in about 1:30 p.m. The caller directed the deliveryman to a rural spot along a main drag, where a gravel road leads to a television transmission tower.

Brian Wells set out to deliver the order for two pies -- sausage and pepperoni -- to the address, then turned up about an hour later and about two miles away at a PNC Bank branch in Summit Township, with a note demanding money and saying he had a bomb.

Wells took the undisclosed amount of money from a teller, got into his car and was surrounded by police a short time later in a parking lot. State troopers pulled him out of the car and handcuffed him. Hanging from his neck under his T-shirt was a triple-banded metal collar and a device with a locking mechanism that kept it in place. Attached to the collar was a bomb.

"It's going to go off," Wells said. "I'm not lying."

Someone -- he apparently did not say who, if he knew -- had started a timer on the bomb, Wells said, and forced him to rob the bank. "Avoid panicking the tellers or customers," said a nine-page note recovered from the car, although it warned: "Use the weapon if anyone does not cooperate or attempts to leave the bank."

As the deliveryman, 46, sat handcuffed on the ground in front of his car while police waited for the bomb squad, the device exploded, killing him -- exactly 40 minutes after he entered the bank. Police found a gun resembling a cane in the car.

Was Wells duped into committing the bank robbery after his last delivery, as he claimed in the moments before his death? Or was he a willing participant? The mystery surrounding that series of events of more than a year ago has yielded more questions than clues and has rallied the Wells family to clear his name, something federal authorities are not ready to do.

"Pretty much, we're looking forward to the day when everyone responsible for Brian's death is brought to justice," Wells's brother, John Wells, said in a telephone interview from his home in Glendale, Ariz.

Wells's sister, Jean Heid, begged for information in an e-mail statement the day before the Aug. 28 anniversary, when the FBI released more portions of the nine-page note and doubled the reward to $100,000.

"It is so difficult for me to believe that someone's heart could be so hardened as to continue to leave our family with so much grief," Heid said. "Please don't be afraid to come forward, in confidence, if you know who took Brian's life. You hold the 'key' to 'unlock' our grief and heal our pain. If you, who killed my brother, is/are alive and are reading this, please come forward to personally receive my and God's forgiveness."

FBI Special Agent Bob Rudge, the lead investigator and second in command of the bureau's Pittsburgh office, said that he understands the family's frustrations but that Wells cannot be ruled out until other suspects are found.

"We are conducting the investigation as if he were a homicide victim . . . but we can't say with certainty" that Wells was a victim, Rudge said.

Two agents are assigned full time to the case, which is also being investigated by the Bureau of Alcohol, Tobacco, Firearms and Explosives and the Pennsylvania State Police. Investigators have pored over nearly 1,000 tips, Rudge said. While most came soon after Wells's death, he said, one or two dribble in each week.

The FBI dubbed the person believed to be behind the crime the "Collarbomber," and Rudge said he "has left his blueprint of his personality on every aspect of the crime."

"FBI analysts believe that Collarbomber has written other letters over his lifetime with similar themes of power, control, ultimatums, limited options, wanting revenge and dire consequences if his demands are not met," Rudge said. "The letter could have gone to banks, businesses or individuals as part of some real or perceived injustice."

"ACT NOW, THINK LATER OR YOU WILL DIE!" the note said.

Erie County Coroner Lyell Cook waited until February to rule Wells's death a homicide, hoping more evidence might warrant a different finding. He based the ruling on the definition that homicide is death at the hands of another.

That does not mean that Wells was not involved, Cook said, though that is based on his gut feeling, not evidence.

"The part of the case that is so maddening for everybody is there is so much evidence, but evidence is only useful when it can be linked to other things," he said.

Portions of the note reveal a controlling personality whose main motive may have been revenge, not money, the FBI said.

Among the author's "rules," listed in numerical order: "Stay calm and do as instructed to survive."

The FBI believes the author constructed the bomb and cane gun.

Cook said the note was gamelike in that Wells was instructed to travel to four locations on Aug. 28, 2003, and was given 55 minutes to complete a series of tasks before he would be able to disarm the bomb.

But authorities said there was not enough time to make all the stops. The first 911 call about the bank robbery was recorded at 2:38 p.m.; the bomb went off 40 minutes later.

The FBI investigated William Rothstein, who lived next to the entrance of the road where Wells delivered the pizzas and emerged with the bomb around his neck. But agents found no evidence to link Rothstein to the bomb, Rudge said.

Questioned immediately after Wells's death, Rothstein kept at least one secret from investigators: He had a body in his freezer.

About a month later, Rothstein came forward with a claim that his former girlfriend had shot a man named James Roden five weeks earlier and that he had helped dispose of the body and clean up the bedroom where the shooting occurred. The woman, Marjorie Diehl-Armstrong, is charged with homicide.

Rothstein died of cancer July 30.

The coroner said he believes there was a connection between Rothstein and the robbery. Descriptions of Rothstein as eccentric, brilliant and one who tinkered with electronics and mechanics are too much of a coincidence, Cook said.

Cook said that although people are transfixed by the mystery, the loss of life has been forgotten.

"Mr. Wells will forever be known as the 'Pizza Bomber,' " he said.

The locking device in this photo was attached to a collar on Wells. Police were awaiting the bomb squad outside the bank when Wells was killed.Brian Wells demanded money shortly before the fatal explosion.