AUSTIN - Hours after Austin Police Chief Brian Manley gave an update on the investigation into a series of package bombs, a fourth explosion was added to the investigation.
Authorities were called to a home on the Southwest Side of Austin around 8:30 p.m. Sunday for a report of an explosion. Dozens of federal investigators have been at the scene of the bombing since.
Authorities shut the area down, urging residents to remain in their homes to give investigators a chance to inspect the blast site.
Richard Herrington lives near the bombing and said he heard it over the NCAA basketball game. Herrington, a military veteran, said he recognized the sound.
"I knew it was a bomb because it was a 'thump,' like a mortar," Herrington said.
The bomb caused serious injuries to two men in their 20s. Manley said a trip wire was used in the bombing and the pair was either walking their bikes down the road or riding them when they hit the trip wire.
Herrington said the blast occurred near the park he and his granddaughter had left only hours before.
"What if that had been our granddaughter that just ran down the street to get into the shade?" Herrington speculated.
Many speculated the bombings could be racially motivated after the first three explosions injured or killed people of color.
"Now we know it's not a hate crime," Herrington said. "There's some other devious motivation."
Another resident said it's paralyzing to think of the bomber's lack of regard for human life, adding that the person could strike anywhere at any time.
"I think the police, FBI, ATF are all doing a great job," one neighbor said. "Hopefully they'll do a great job catching them."
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