OMAHA, Neb. - Less than six months after an anthrax scare rocked the U.S. Postal Service, mail carriers have a new form of terrorism on their hands: pipe bombs. <br>
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Mail carriers were expected to return to their routes Monday with a heightened sense of caution following the discovery of 15 mailbox pipe bombs across the Midwest since Friday, authorities said. <br>
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The postal service asked customers in Nebraska, Iowa and northwest Illinois with roadside delivery to secure their mailbox doors open or remove the doors to ensure service. <br>
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"We are instructing our carriers not to deliver to any closed receptacles," said Mike Matuzek, U.S. Postal Service district manager for Nebraska and southwest Iowa. <br>
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Matuzek called it a temporary precaution while the investigation continues. Locked mailboxes like the ones in post offices will have normal mail delivery. <br>
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"It is deplorable," he said. "It brings a lot of innocent people into the fray of this thing where they really don't belong." <br>
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Six people were injured by explosions in Illinois and Iowa on Friday. Two other bombs found in Iowa did not explode. Then, six bombs were found Saturday in rural areas of Nebraska, and a seventh was found Sunday. They were all later detonated harmlessly by authorities. <br>
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An anti-government note found with the bombs warned of more "attention getters," and federal authorities described the bombs as an act of domestic terrorism. <br>
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"The individual claims that they're trying to contact the government or get in touch with them, but using a means like this with pipe bombs ... that's not the way to get the message across," FBI agent Jim Bogner told CBS' "The Early Show." <br>
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In addition to the real bombs, one fake bomb was found Sunday in Nebraska, and 18-year-old man was arrested in the prank, the U.S. Postal Service said. <br>
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Roger Humphries, a postal service spokesman, declined to describe the latest devices. The Postal Service doesn't want to deal with any more hoaxes, he said. <br>
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Officials on Sunday renewed pleas that whoever planted the bombs contact them and make their grievances clear. <br>
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"I hope whoever is responsible would respond," said Thayer County Sheriff David Lee, whose department received a call on one bomb found in a rural mailbox near Davenport on Saturday. <br>
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Postal officials said the bombs were accompanied by typewritten notes in clear plastic bags that said, in part: <br>
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"If the government controls what you want to do they control what you can do. ... I'm obtaining your attention in the only way I can. More info is on its way. More 'attention getters' are on the way." <br>
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Lee's request on Sunday that the bomber contact authorities followed a similar message from the FBI on Saturday. <br>
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"You have gotten our attention. We are not certain we understand your message. We would like to hear from you. We are listening," said Weysan Dun, assistant special agent-in-charge of the FBI's Omaha office. "You do not need to send any more attention getters." <br>
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Officials described the bombs as three-quarter-inch steel pipes attached to a 9-volt battery, and said they appeared to be triggered by being touched or moved. <br>
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Among the six people injured Friday, only a 61-year-old woman remained hospitalized Sunday. Doris Zimmerman, who lives near Anamosa, Iowa, was listed in fair condition. <br>
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Mail carrier Lyle Bartels of Ohiowa, Neb., said he'll be cautious when he returns to his route. Two of the pipe bombs found Saturday were in his delivery area. <br>
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"I'm just going to try to look the boxes over a little bit before I open them," Bartels said. "It's kind of scary."