The wife of a software engineer who crashed his plane into an office building that held more than 200 federal tax agency employees said she is sorry for everyone affected by the tragedy, The Associated Press quoted a family spokesperson.
Rayford Walker said he's a spokesman for Joseph Stack's family. He read a statement from Stack's wife, Sheryl Stack, while standing in front of a house across the street from the Stack home. The Stack home was set on fire Thursday before Joseph Stack crashed his plane into the building.
In the statement, Sheryl Stack thanks her friends and family and offers her "sincerest sympathy" for the victims and their families. She also says she won't comment further.
Authorities say Joseph Stack III was angry with the government and crashed his plane into the building. He killed himself and one person in the building.
Stack left behind a rambling anti-government manifesto, but otherwise offered little indication that he was planning such an attack.
The National Transportation Safety Board (NTSB) has transferred control of the investigation to
the Federal Bureau of Investigation.
A. Joseph Stack III posted his angry screed on a Web site registered to him before he flew a single engine plane into the hulking black-glass Echelon 1 building on Thursday, killing himself and at least one worker. Stack, 53, apparently targeted the building's lower floors, which housed local offices of the Internal Revenue Service.
An IRS worker, Vernon Hunter, 67, was killed in the crash. Vernon was a Revenue Office Manager responsible for collections. His wife Valerie also works for the IRS and was in the building when the plane struck.
On Friday, police and fire investigators picked through the wreckage at the office building and at Stack's red brick home about six miles away — which Stack apparently set fire to before taking off his his plane. The home's roof had caved in and its windows had blown out.
U.S. law enforcement officials also said they were trying to determine if Stack put anything in the plane to worsen the damage caused by the impact and fire.
His wife, Sheryl Stack, was expected to address the news media on Friday although it was unclear when or how, the Red Cross said. One law enforcement official said investigators were trying to find out if a marital dispute precipitated Stack's angry suicide mission. All officials spoke on condition of anonymity because the investigation was ongoing.
In his self-described "rant," Stack railed against "big brother," the Catholic Church, the "unthinkable atrocities" committed by big business and the governments bailouts that followed.
In the note, signed "Joe Stack (1956-2010)" and dated Thursday, he said he slowly came to the conclusion that "violence not only is the answer, it is the only answer."
Law enforcement officials, speaking on condition of anonymity because the investigation was still going on, said Stack apparently posted the screed and set fire to his house before leaving for the airport.
Some who knew Stack said he offered little hint of his anger.
"He didn't rant about anything," said Pam Parker, an Austin attorney whose husband played in a band with Stack. "He wasn't obsessed with the government or any of that. ... Not a loner, not off in a corner. He had friends and conversation and ordinary stuff."
But in his posting, Stack fumed about the IRS and wrote, "Nothing changes unless there is a body count."
"I have had all I can stand," he wrote, adding: "I choose not to keep looking over my shoulder at `big brother' while he strips my carcass."
Stack took off from Georgetown Municipal Airport, about 30 miles from Austin, at 9: 40 a.m. ET and flew low over the Austin skyline before plowing into the side of the Echelon 1 office building just before 10 a.m. ET. Flames shot from the building, windows exploded and terrified workers rushed to get out.
Federal Aviation Administration spokesman Lynn Lunsford said Stack didn't file a flight plan.
The Pentagon scrambled two F-16 fighter jets to patrol the skies over the burning building before it became clear it was the act of a lone pilot, and President Barack Obama was briefed.
"It felt like a bomb blew off," said Peggy Walker, an IRS revenue officer who was sitting at her desk. "The ceiling caved in and windows blew in. We got up and ran."
IRS Agent William Winnie said he was on the third floor of the building when he saw a light-colored, single engine plane coming toward the building, TheStatesman.com reported.
“It looked like it was coming right in my window,” Winnie said, according to the Web site.
He said the plane veered down and smashed into the lower floors. “I didn’t lose my footing, but it was enough to knock people who were sitting to the floor,” he said.
Emergency crews originally said people were missing inside the building, but later recovered two bodies. Austin Fire Department Battalion Chief Palmer Buck declined to discuss the identities of those found, but said authorities had now "accounted for everybody."
Thirteen people were injured, authorities said. One man remained hospitalized Friday at Brooke Army Medical Center in San Antonio with burns and was in stable condition, the hospital said.
The FBI launched an investigation and Rep. Michael McCaul, a Republican from Austin on the Homeland Security Committee, said the panel will take up the issue of how to better protect buildings from attacks with planes.
Patrick Beach, who once played in a band with Stack, described him as a mild-mannered guy who was a stereotypical software guy.
"I talked to a lot of people who knew him better than I did, and no one saw anything like this coming," Beach told Fox News.
The toughest part about this, Beach said, was how this guy, who loved his wife and step-child, could be the same person who wanted to "commit mass murder."
Stack's Web tirade begins: "If you're reading this, you're no doubt asking yourself, `Why did this have to happen?"'
He recounts his financial reverses, his difficulty finding work in Austin, and at least two clashes with the IRS, one of them after he filed no return because, he said, he had no income, the other after he failed to report his wife's income.
According to California state records, Stack had a troubled business history, twice starting software companies in California that ultimately were suspended by the state's tax board, one in 2000, the other in 2004. Also, his first wife filed for bankruptcy in 1999, listing a debt to the IRS of nearly $126,000.
Stack's father-in-law, Jack Cook, told The New York Times that he knew Stack had a "hang-up" with the IRS and his marriage had been strained. His wife had taken her daughter to a hotel to get away from Stack on Wednesday night, the newspaper said.
Thursday was not the first time a tax protester went after an Austin IRS building. In 1995, Charles Ray Polk plotted to bomb the IRS Austin Service Center. He was released from prison in October of last year.
The tax protest movement has a long history in the U.S. and was a strong component of anti-government sentiments that surged during the 1990s. That wave culminated in the 1995 bombing of a federal building in Oklahoma City that killed 168 people. Several domestic extremists were later convicted in the plot.
The Associated Press contributed to this report.