Two more pipe bombs, one a hoax, in Nebraska

A technician carrying a remote trigger prepares to explode a pipe bomb found Saturday in a rural Nebraska mailbox.

OMAHA, Nebraska (CNN) -- Authorities in Nebraska responded Sunday to reports of two more mailbox pipe bombs -- one of which turned out to be a hoax -- one day after six such devices were found in rural mailboxes across the state, the Nebraska State Patrol said.

Excluding the hoax, a total of 15 bombs have been discovered in mailboxes in mostly rural areas of Nebraska, Illinois and Iowa. While none of the devices in Nebraska detonated, six bombs exploded in the other two states on Friday, wounding four postal employees and two elderly residents.

Federal authorities have said the incidents amounted to "domestic terrorism."

The first such report Sunday originated in St. Paul, near the town of Dannebrog, where a pipe bomb was discovered the previous day, according to state patrol spokeswoman Terri Teuber. Investigators later concluded the device was a toy, and St. Paul police were interviewing a juvenile suspect in connection with the case.

CNN NewsPass VIDEO U.S. Postal Service Inspector Linda Jensen warns not to touch the devices or slam mailbox doors shut (May 3) Play video   EXTRA INFORMATION • Map: Pipe bomb terror  • Mailbox bomb letter text

Bomb technicians were on their way to Boone County, just outside Albion, to examine the second reported pipe bomb, Teuber said. Albion is located between the towns of Scotia and Columbus, where two bombs were found Saturday.

Just after midnight Saturday, authorities detonated a pipe bomb outside a home in Seward, Nebraska, Teuber said. Except for the Albion device, all the bombs have been "rendered safe," she said, with some detonated by authorities and others disassembled.

The Iowa and Illinois cases have, thus far, proven more harmful, with six of eight bombs found in those states exploding before authorities could safely detonate or defuse them.

Anti-government notes found with Friday bombs

An investigator takes photos of a crime scene where a bomb exploded Friday after a rural mail carrier opened a mailbox north of Dubuque, Iowa.

In addition to Seward and Albion, the Nebraska devices were found in Columbus, Ohiowa, Davenport, Dannebrog and Scotia -- all in the eastern part of the state but spread over a wide area.

At least one of the devices found Saturday was accompanied by a note. "And it appears some of the other devices may as well" have notes, said FBI Special Agent Weysan Dun.

The devices in Illinois and Iowa were accompanied by clear plastic Ziploc-type bags, each containing a typewritten letter full of anti-government statements, officials said.

Authorities are working to determine the contents of the note, which was damaged when the device was "made safe," Dun said.

A note with one of Friday's bombs said, "I'm obtaining your attention in the only way I can. More info. will be delivered to various locations around the country." Much of the note spoke against the U.S. government. (Read the note)

Addressing whoever was responsible for the bombs, Dun said, "We are not certain we understand your message, and we would like to hear from you. We are listening, and you do not need to send any more attention-getters because you have our attention."

Citizens urged to be alert, cautious

Gov. Mike Johanns urged Nebraskans to be cautious. "If they see something that does not look right, needless to say they should not investigate on their own," Johanns said. "Call the local sheriff or police and get us involved immediately."

He also made a plea to the person or persons responsible. "We have heard from you, and we ask that you reach us without any more effort like this," he said.

None of the devices found Friday or Saturday had been sent through the mail, Dun said. "It is our belief that they were physically placed into the mailboxes," he said.

The pipes were about 1 inch in diameter and 6 inches long, "in some cases with wires or a battery or something like that," Dun said.

What remains of the explosive devices will be sent to an FBI laboratory for analysis, he said.

Jon Petersen, Bureau of Alcohol, Tobacco and Firearms resident agent in charge, said authorities had "a number of promising leads [that] have already been received by the task force and are being vigorously pursued."

Friday's devices appeared to have been rigged to detonate when the mailboxes were opened, Postal Inspector Linda Jensen said. Carriers on routes from Cedar Rapids, Iowa, east into Illinois were called back, and Saturday mail delivery was suspended.

There were no plans to suspend the delivery of mail Monday, said Dave Margritz, a U.S. postal inspector in Omaha.