Marjorie Diehl-Armstrong, who is already imprisoned for killing her boyfriend, was notified that she may face charges of bank robbery and conspiracy and a firearms count, lawyer Lawrence D'Ambrosio said. He says Diehl-Armstrong is innocent.
The Erie Times-News, citing an unnamed source, reported that an acquaintance of Diehl-Armstrong was also notified that he could face similar charges.
Still not known is whether deliveryman Brian Wells was part of the plot, reports CBS News correspondent Cynthia Bowers.
The U.S. attorney's office would not comment on the case but said a news conference was scheduled for Wednesday to announce a "major development."
On Aug. 28, 2003, 46-year-old Wells set out to deliver an order for two pizzas to a mysterious address that turned out to be the location of a TV tower. He turned up about an hour later and roughly 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 money from a teller, got into his car and was soon captured by police. 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 had started a timer on the bomb, Wells said, and forced him to rob the bank.
While police waited for the bomb squad, the bomb exploded, killing Wells. Police found a gun resembling a cane in the car and a nine-page rambling handwritten letter that included detailed instructions on what Wells was to do with the bank money and how he could unlock the collar by going through a kind of scavenger hunt, looking for clues and landmarks.
The note also included a list of rules and a threat that Wells would be "destroyed" if he failed to complete his mission.
Diehl-Armstrong, 58, has been linked to the Wells investigation because her boyfriend's body was found in the freezer of a home near the TV tower where Wells made his final delivery. She pleaded guilty but mentally ill to killing her boyfriend and is serving a sentence of seven to 20 years in state prison.
The man who owned the home, William Rothstein, was questioned in Wells' death but has since died of cancer.
Authorities have never said whether they believe Wells was an innocent victim, a conspirator or someone who knew something about the robbery plot but did not realize the risk he faced. Wells' family believes he was just a victim.
D'Ambrosio, Diehl-Armstrong's attorney, has said he believes she had nothing to do with Wells' death but may have known the people behind the robbery.