John P. Tomkins, 42, of Dubuque, Iowa, was arrested on his way to work, and federal agents began searching his home and a storage facility, the U.S. attorney's office said.
Investigators, led by U.S. Postal Inspectors, say Tomkins, who lived in a suburban home with his wife and three school-aged children, has been directly linked to 16 threatening letters and two pipe bombs mailed by "The Bishop" to financial firms over the past two years, reports CBS News correspondent Bob Orr. The bombs mailed in January were deliberately left disconnected but carried the ominous warnings: "Bang you're dead."
A criminal complaint unsealed in Chicago charged Tomkins with one count of mailing a threatening communication with intent to extort and one count of possession of an unregistered explosive device. Officials said the pipe bombs would have exploded had just one wire been connected.
"We take it quite seriously if anyone goes out and tries to mail threatening communications to people to affect the stock market," U.S. Attorney Patrick Fitzgerald said at a Chicago news conference.
A telephone message left at a number listed for a John Tomkins in Dubuque wasn't immediately returned. He was scheduled to appear in court in Chicago later Wednesday.
Investigators have said "The Bishop" mailed more than a dozen letters to financial institutions for 18 months. The letters included references to heaven and hell and threatened recipients if the prices of certain stocks did not move to certain levels, often $6.66; the number "666" is associated with Satan.
"The way I see it, you owe it to us to make things right or I will make your life as miserable as mine is," one of the letters read.
Tomkins is a former substitute letter carrier who worked weekends for the U.S. Postal Service, authorities said. They said he was not an employee at the time the devices were sent.
An affidavit filed with the court by postal inspectors said two parcels with the pipe bombs inside were mailed Jan. 26 from Rolling Meadows, Ill., in Chicago's northwest suburbs.
One was addressed to an individual at Janus Small Cap, a mutual fund, and at an address in Denver, officials said. That parcel was later forwarded to an office in Chicago. They said the other package was addressed to a person at American Century in Kansas City, Mo.
Each contained what appeared to be a booby-trapped pipe bomb, officials said. They said that the firing circuit was not fully connected, otherwise the devices would have exploded, sending out a potentially fatal spray of fragments.
Authorities quoted the letter as saying that there would be a rally in the stock price of Navarre Corp., a technology and entertainment company.
The affidavit describes 16 other letters signed "The Bishop."
Among those other letters was one postmarked Palatine, another Chicago suburb, on June 9, 2006, addressed to investment management executives that said: "TIMES UP ... IT IS BETTER TO REIGN IN HELL, THAN TO SERVE IN HEAVEN ... THE BISHOP."
One letter postmarked March 13, 2006, was addressed to a senior officer of Navarre Corp., complaining about the executive's pay and a decline in the stock price, officials said.
They quoted the letter as saying: "Within the next 60 days you are going to find a way to reverse the downward spiral of the stock price or the devil will be paying you a visit." It ended with the words "tic-toc" and was signed "The Bishop."
Officials said Tomkins' handwriting samples matched the writing on some of the envelopes that The Bishop mailed and a debit card receipt put him in Florida near the time three Bishop letters were mailed from Orlando, reports Orr.
In addition, agents determined from a photograph contained in one of the mailings that the man they were looking for may have been driving a 1993, four-door Chevrolet Lumina — the kind of car Tomkins owns.
Sales records from a home improvement store in Dubuque show that in December 2006, materials similar to those used in the pipe bombs were purchased with Tomkins' credit card, the affidavit said.
A conviction for mailing a threatening communication with intent to extort carries a maximum sentence of 20 years in prison, and for possession of an unregistered destructive device carries a maximum of 10 years.
Kenneth T. Laag, inspector in charge of the Chicago division of the Postal Inspection Service, said investigators worked with the FBI Terrorism Task Force on the case. He said the team analyzed complex financial records and used forensic science to track down Tomkins.