AUSTIN BOMBINGS: Bomber uses readily available materials

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The person who is making explosive devices and has left them at three Austin doorsteps is constructing them using common household items that can be easily purchased at hardware stores, potentially making efforts to identify the perpetrator more difficult, law enforcement officials said Thursday.

Authorities are trying to identify all the materials used to make the bombs, which have killed two people and left an elderly woman seriously wounded. However, they do not think the bombs were built from specialized equipment that would enable them to more easily identify who would have access to such items.

Federal agents this week have been visiting local stores trying to determine if a customer purchased items that appear suspicious, but so far have not gained information to lead them to a possible suspect, the sources said.

How the bombs were manufactured remains a focus of the investigation as officials also pursue other avenues, including going through hours of video surveillance gathered by neighbors who have security cameras. Testing on remnants of the explosive devices is being performed by the federal Bureau of Alcohol, Tobacco, Firearms and Explosives.

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Tina Sherrow, who retired last year from the ATF as a senior special agent and explosives specialist, said it is more difficult for investigators to track down bomb makers who use common items.

“The resources to make such devices with components can be as simple as going to the stores, it’s as simple as going under your kitchen sink, or going to your garage or getting them online,” Sherrow said. “It does make it a little more difficult if it’s just your random bolt box from China on the shelf of Home Depot.”

Stores that sell such items include Lowe’s, Best Buy and Radio Shack. People can use household chemicals, fireworks or shotgun shell powder for explosives. Sherrow has even seen juveniles load a pipe bomb with the heads of match sticks.

To track devices made with common parts, investigators make a list of the items found at the scene, such as cleaning chemicals, specific types of nails used to create shrapnel and branded electronic components. Then they go to stores in the area that sell those items and go through their purchase records. Ideally, they will find a receipt with multiple items from the scene and check the store’s video records to get a glimpse of the purchaser. But they often come up empty.

“If you go buy a box of three-penny cut nails at a store, there’s no tracking that,” she said. “Sometimes you get lucky. Sometimes you don’t.”

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For example, Sherrow, who worked for two months on the 1996 Centennial Olympic Park bombing in Atlanta that killed one and injured 11 others, said the bomber, Eric Rudolph, was able to avoid detection for a long time because he used common items in the devices.

Meanwhile, federal agents continue to pursue the connections between victims.

The American-Statesman reported Wednesday that Anthony House, the first person killed when a bomb exploded on his porch, is the son of the Rev. Freddie Dixon. Dixon is a close friend of Norman Mason, the grandfather of 17-year-old Draylen Mason, who was killed Monday morning in the second package bomb attack.

Both Dixon and Mason are prominent members of Austin’s African-American community.

Agents also talked to a woman named Erica Mason, whose neighbor was injured in one of the package explosions. Mason, who is from Iowa, isn’t related to the Mason family prominent in the local African-American community. But police have developed a theory that the bomber might have mistaken her for another member of that family.

READ: Police question Austin woman they think might have been bombing target

If the theory proves true, the bomber made two mistakes: targeting the wrong Mason and accidentally placing the package a few doors down — at the house of Maria Moreno, whose 75-year-old daughter Esperanza Herrera was critically injured after picking it up.

Since the two blasts Monday morning, Austin police have received more than 500 reports of suspicious packages, none of which have proven to be dangerous.

Police, however, are still urging anyone who encounters a suspicious package to call 911 immediately, and not to touch or handle the package.

Authorities say people should look out for packages with misspelled words, no return address, strange odors, restrictive markings or exposed wires.

Officials are offering up to $65,000 to anyone who comes forward with information leading to the arrest of the person responsible for the attacks.

Anonymous tips can be submitted to the local Crime Stoppers tip line at 512-472-8477 or the state tip line at 1-800-252-8477.

Staff writer Mark D. Wilson contributed to this report.