Joseph A Stack, a software engineer, flew his small single-engine Piper Cherokee aircraft into the Echelon building in north Austin, which houses the offices of the Internal Revenue Service — the US tax collection service — shortly before 10am.

The US Department of Homeland Security said that it was a "deliberate criminal act" and that Mr Stack was the registered owner of the aircraft.

In a lengthy manifesto posted on a website he administered, he recounted his numerous struggles with the IRS and concludes: “I am finally ready to stop this insanity. Well, Mr Big Brother IRS man, let’s try something different; take my pound of flesh and sleep well.”

The remainder of the manifesto reads like the angry, frustrated ramblings of a man who felt ignored by his Government and the people who were supposed to represent his interests. Mr Stack cites the government bailouts of banks and auto companies and the “murdering [of] tens of thousands” by the greedy insurance companies while his government representatives sit idly by and only help the rich.

Mr Stack added: “I can say with a great degree of certainty that there has never been a politician cast a vote on any matter with the likes of me or my interests in mind. Nor, for that matter, are they the least bit interested in me or anything I have to say.

“I know I’m hardly the first one to decide I have had all I can stand,” Mr Stack wrote before declaring: “I also know that by not adding my body to the count, I insure [sic] nothing will change.”

His aircraft took off from Georgetown airport, about 40 minutes north of Austin. Witnesses said that they saw the aircraft flying low towards the centre of the Echelon building at full speed, skimming over traffic lights, before crashing into the building.

Homeland Security officials said the act was not connected to terrorism, but that the F16 Air Force jets had been scrambled “due to an abundance of caution”.

More than an hour after impact, flames poured from the smashed windows and thick black smoke filled the air.

Aviation experts expressed shock at the intensity of the flames based on the relatively small amount of fuel the aircraft would have been able to carry, suggesting that Mr Stack may have been carrying some sort of accelerant or explosive on board at the time of impact.

Occupants of the building described the impact as feeling “like an earthquake.” The building complex also reportedly housed offices for the FBI and CIA, but there no evidence to suggest an intent to target those organisations.

Local hospital officials confirmed last night that one of the two people injured in the incident had suffered second-degree burns over about 25 per cent of their body and was transferred to a burn centre, while the other suffered minor smoke inhalation and had been discharged.

The IRS confirmed that it had 190 employees working in the building and that it was still trying to account for all of them for them.

President Obama was briefed on the situation by his counterterrorism chief, John Brennan, before boarding Air Force One, but the White House emphasised that the incident did not appear to be linked to terrorism.

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http://www.timesonline.co.uk/tol/news/world/us_and_americas/article7032669.ece

Feb. 19, 2010