The bomb that killed a pizza delivery man after a bank robbery was locked around his neck by a homemade metal collar that an FBI agent described as "unique" and "sophisticated."
Brian Wells, 46, was killed Thursday after authorities said he robbed a bank, warning the tellers he was a human bomb. He died when the bomb exploded after he had been arrested a short distance from the PNC Bank in Erie.
He had told police that someone had started a timer on the bomb and it was set to go off, but police said they were unable to safely defuse the bomb or remove the collar locking it to his body before it went off.
FBI agent Bob Rudge said at a news conference today that the locking device consisted of four key locks and a combination lock, and appeared to be homemade.
"It is not likely that it was commercially manufactured and not likely it had any legitimate purpose," Rudge said. "Its most likely purpose was attaching the device to the neck of the individual who went into the PNC bank. … The locking mechanism was unique and it was sophisticated."
Investigators at the FBI laboratory in Quantico, Va., who reconstructed the device had not yet determined whether Wells could have locked it into place himself, or whether someone would have had to put it on him, Rudge said.
Photographs of the collar were to be posted on the FBI Web site later today, in the hopes that someone might be able to provide a lead on who made it, Rudge said.
Teams of investigators from a multi-agency task force that includes the FBI, the Pennsylvania State Police, the Erie police, the U.S. Attorney's office and the Erie County District Attorney's office are trying to determine whether Wells was working on his own, was a willing participant in the robbery or was a "bomb hostage," state police Corp. Mark Zaleski said.
Two notes were recovered from the scene, one for bank employees and one for Wells, but authorities refused to discuss the contents of the notes.
Autopsy Provides No Link
A preliminary autopsy report on one of Wells' co-workers who died under mysterious circumstances on Sunday failed to clear up the question of whether there was a link between his death at his home and the bomb that killed Wells, Zaleski said.
On Sunday, family members found the body of Robert Pinetti, 43, another pizza delivery man who worked with Wells, in his Lawrence Park Township home.
Pinetti had refused medical treatment several hours earlier, when family members called an ambulance because they were concerned about his condition, authorities said today.
The preliminary autopsy found evidence of methadone and depressants similar to Valium in Pinetti's system, law enforcement officials said. The combination of the two drugs could lead to an overdose, but it was not yet clear whether that was the cause of his death, and if it was, whether it was accidental or intentional, officials said.
There was no evidence of any trauma or other injury, they said.
Investigators had hoped that the autopsy might help them determine whether there was any connection between the deaths of the two men, but came away with no answer.
"At this time, no connection has been made between the two," Zaleski said. "Investigators are exploring any link."
Police searched Wells' home overnight, and removed 18 boxes of potential evidence, but officials declined to comment on what they found.
The delivery man's landlord described him as "impeccably honest."
Wells allegedly entered a PNC Bank branch in Erie on Thursday, some time after leaving Mama Mia's Pizza-Ria, where both he and Pinetti worked, to deliver two sausage and pepperoni pies to a rural location along a main road, near a television transmission tower.
Bank employees complied with Wells' demands for money after he allegedly told them that an explosive device was strapped to his neck.
The pizza delivery man was arrested minutes later only a quarter of a mile away and handcuffed. He told police the same story he told those at the bank: that he was wearing a bomb.
Authorities immediately backed away to secure the area while an anguished Wells cried, "Why is nobody trying to get this thing off me? He pulled a key out and started a timer. I heard the thing ticking when he did it. It's gonna go off. I don't have a lot of time. I'm not lying."
Moments later the device around his neck went off.
Law enforcement officials said over the weekend they simply did not have time to defuse the bomb safely.
"It's a highly complex procedure," FBI Special Agent Ken McCabe said. "It's not like you see on TV where any police officer can walk up and decide to cut the yellow, green or red wire."
ABCNEWS' John Berman contributed to this report.