5 mailbox pipe bombs found in Nebraska

Incidents a day after similar devices wound 6 in Iowa, Illinois

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

OMAHA, Nebraska (CNN) -- Five pipe bombs were planted in mailboxes in five Nebraska counties Saturday, leading authorities to appeal to those responsible for these devices and similar ones found the previous day in rural Iowa and Illinois not to send any more "attention getters."

"To the individual or individuals responsible for this, ... I would like to say that you have gotten our attention," Weysan Dun of the FBI said. "However, we are not certain we understand your message, and we would like to hear from you."

No one was injured Saturday as none of the devices found in the rural central Nebraska towns of Columbus, Ohiowa, Davenport, Dannenbrog and Ord exploded.

On Friday, six of eight mailbox pipe bombs discovered in northwest Illinois and northeast Iowa did detonate, injuring four postal workers and two elderly Iowa women.

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

"The devices found ... in Nebraska have similarities to those found yesterday," Dun said. "At least one of the devices, the one found in Ohiowa, has a note associated with it, and it appears that some of the other devices may as well."

While authorities in Nebraska said they were still working to determine the contents of the Ohiowa message, investigators have said a plastic bag containing a typewritten letter accompanied each bomb discovered Friday. (Read the note)

The letters were either the same or contained similar anti-government statements and promised more "attention getters" on the way, FBI Special Agent James Bogner said Friday.

"We looked at the letter that had accompanied the devices and are viewing it as a domestic terrorism incident," Bogner said.

None of the pipe bombs found in rural, residential mailboxes in all three states was sent via the U.S. Postal Service, said Dun, indicating the devices had been physically placed.

Many 'promising leads' into Friday incidents

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

Authorities looking into the Illinois and Iowa pipe bomb cases have "a number of promising leads [that] have already been received by the task force and are being vigorously pursued," ATF Resident in Charge Jon Petersen said.

The pipe bombs found Friday -- placed in primarily rural areas of the two states -- were made from three-quarter-inch pipes with a 9-volt battery attached. The devices discovered in Nebraska had similar characteristics, Dun said.

Officials said Friday that the bombs appear to have been placed in mailboxes randomly, and no threats were phoned into authorities. (Full story)

"At this point, it appears as though the explosives devices were intended to detonate when they were removed from rural boxes, mailboxes," U.S. Postal Inspector Linda Jensen said.

Nebraska Gov. Mike Johanns urged citizens to be alert, advising them to contact local authorities immediately "if they see something that doesn't look right."

Customers who find suspicious items or notice someone putting things in mailboxes are urged to call the local police or the postal inspection service command center in St. Louis at (314) 539-9310 and immediately clear the area around the mailbox.

Dun also said anyone with information about the case could contact the FBI's branch in Omaha at (402) 493-8688.

The FBI, ATF, U.S. Postal Inspection Service, Nebraska State Patrol and various local and country law enforcement agencies are cooperating in the Nebraska case.

A similar group has been put together in Illinois, including officials from the Customs Service, Immigration and Naturalization Service and Secret Service.

The ATF, FBI, U.S. Postal Inspection Service, U.S. Attorney for the Northern District of Iowa and Iowa law enforcement officials formed a joint task force Saturday to investigate the bombs in that state.