Mark Anthony Conditt, an unemployed college dropout who bought bomb-making materials at Home Depot, was tracked down using store surveillance video, cell phone signals and witness accounts of a customer shipping packages in a disguise that included a blonde wig and gloves.
His motive remained a mystery.
Police finally found the 23-year-old early Wednesday at a hotel in a suburb north of Austin known as the scene for filming portions of "Friday Night Lights." Officers prepared to move in for an arrest. When the suspect's sport utility vehicle began to drive away, they followed.
Conditt ran into a ditch on the side of the road, and SWAT officers approached. That's when he detonated a bomb inside the vehicle, Austin Police Chief Brian Manley said.
Police discovered a 25-minute video recording on a cellphone found with Conditt, which Manley said he considers a "confession" to the bombings, It described in great detail the differences among the bombs, he said.
"What is clear, from listening to that video is this was a very troubled young man who was talking about challenges in his life that lead him to the point where he took the actions that he took," Manley said of the recording.
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The confession was obtained after a frightening altercation Wednesday morning.
They say Conditt didn't know the victims, or use hate, or terrorism as a motive.
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Here’s a look at the Austin bomber’s car. Police say Mark Conditt, the 23 yo suspect, blew himself up. Officers say he’s tied to five other explosions, some deadly. @abc13houston pic.twitter.com/Z8D6CmbBBp— Marla Carter (@MarlaABC13) March 21, 2018
Law enforcement officials did not immediately say whether Conditt acted alone in the five bombings in the Texas capital and suburban San Antonio that killed two people and badly wounded four others.
Investigators released few details about Conditt, except his age and that he was white. Neighbors say he was home schooled. He later attended Austin Community College from 2010 to 2012, according to a college spokeswoman, but he did not graduate.
In posts dated from 2012, a blogger who identified himself as Mark Conditt of suburban Pflugerville wrote that gay marriage should be illegal. He also called for the elimination of sex offender registrations and argued in favor of the death penalty. He listed his interests as cycling, tennis and listening to music.
Of gay marriage, Conditt wrote: "Homosexuality is not natural. Just look at the male and female bodies. They are obviously designed to couple."
Jay Schulze, who lives in Pflugerville, said he was jogging Tuesday night when he was stopped by police and asked about the bombings. He said police flew drones over Conditt's home for about six hours between Tuesday evening and early Wednesday morning.
Schulze described the home as "a weird house with a lot of people coming and going" and a bit rundown.
A neighbor who watched Conditt grow up said he always seemed smart and polite. Jeff Reeb said he has lived next to Conditt's parents for about 17 years and described them as good neighbors. Conditt had visited his parents regularly, he said.
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Conditt's family released a statement saying they had "no idea of the darkness that Mark must have been in." His uncle, Mike Courtney, said his nephew was a "computer geek" who was intelligent and kind.
Austin was hit with four bombings starting on March 2. The first explosions were from packages left on doorsteps. Then a bomb with a tripwire was placed near a public trail. A fifth parcel bomb detonated early Tuesday at a FedEx distribution center near San Antonio.
Rep. Michael McCaul, a Republican from Austin, said Conditt's "fatal mistake" was walking into a FedEx store to mail a package because that allowed authorities to obtain surveillance video that showed him and his vehicle, along with his license plate number. From there, investigators could identify the suspect and eventually track him using his cellphone.
Police warned of the possibility that more bombs had yet to be found.
"We don't know where this suspect has spent his last 24 hours, and therefore we still need to remain vigilant to ensure that no other packages or devices have been left to the community," Manley said.
By late afternoon, federal officials had a "reasonable level of certainty" that there were no more package bombs "out in the public," said Fred Milanowski of the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives. But authorities urged continued awareness just in case.
"We think we're on top of this, but we just don't know," FBI agent Chris Combs said.
Homemade explosives were recovered from Conditt's home. His two roommates were detained for questioning. One was later released.
AUSTIN BOMBING SUSPECT IS DEAD. Great job by law enforcement and all concerned!— Donald J. Trump (@realDonaldTrump) March 21, 2018
To say all of your colleagues across the Nation are proud of you, @Austin_Police, @ATFHou, @FBI & all who worked courageously & tirelessly, would be understatement. Now let’s remove that interim title & build the Department which is long overdue. Congratulations. https://t.co/fjdwxnWzIA— Chief Art Acevedo (@ArtAcevedo) March 21, 2018
Investigators said one room in the home contained bomb components and explosive materials but no finished bombs. They were analyzing Conditt's internet history to find out how he learned to make bombs.
Police initially believed the bombings may have been hate crimes because the victims of the earliest blasts were black, but they backed off that theory after Hispanic and white victims from different parts of the city were also affected.
Milanowski, the agent in charge of the Houston division of the ATF, said it was "hard to say" if the bombing suspect had acted alone. Investigators were confident that "the same person built each one of these devices."
Isaac Figueroa said he and his brother heard sirens and helicopters around 2 a.m. Wednesday in the area and drove toward them, then cut through nearby woods on foot after they hit a police roadblock.
The 26-year-old said they saw a sport utility vehicle that was pinned between large vans and "looked like it had been rammed off the road." He said police later deployed a robot to go examine the vehicle.
The suspect's death followed a day of rapid-fire developments in the case. On Tuesday, the bomb at the FedEx shipping center in suburban San Antonio exploded on a conveyer belt.
Later, police sent a bomb squad to a FedEx facility outside the Austin airport to check on a suspicious package. Authorities subsequently said that package contained an explosive that was tied to the other bombings.
Officers then recovered footage of Conditt wearing a blonde wig and gloves as he turned over packages to send at a FedEx store in south Austin. That was enough to set in motion the manhunt that ended with Wednesday's fatal explosion.