Michael McDermott thought his employer should not be colluding with the tax authorities in docking his wages for back tax. He told the accounts department of Edgewater Technologies Inc as much last week in no uncertain terms. To no avail.
So McDermott, who had been undergoing psychiatric care in a local Massachusetts hospital, took his AK 47 semi-automatic assault rifle, a 12-gauge shotgun, and a semi-automatic pistol to work with him on Tuesday and shot dead seven work-mates: four women, three men.
Yesterday the burly 42-yearold software engineer, sat impassively in the dock of Malden District Court as the local assistant district attorney, Mr Tom Reilly, described the killings one by one. Through his lawyer he pleaded "not guilty" and was remanded on bail.
"Mucko", as he is known to colleagues, said nothing. A giant bear of a man at six feet, three inches and weighing some 20 stones, with a massive mane of dark hair and a bushy beard, he could have been cast as Grizzly Adams. The slaughter is the worst mass killing in Middlesex County's history and the first murder in the quiet Boston suburb of Wakefield for 12 years.
The shootings has have already ignited local anger at the ease with which McDermott acquired his illegally held guns in a state which has the toughest licensing requirements in the US. Mr Reilly told the court that police had also found another rifle at McDermott's workplace, with several boxes of ammunition, and in searching his home had recovered a number of detonators and some nitro glycerine.
What was clear is that McDermott, who had spoken casually to other workmates after his unremarkable arrival at work, at 11.00 a.m. had gone on a shooting spree. He killed two staff members in the company's reception area, one of them a human resources director of Edgewater, before moving to the human resources office. There he killed two workers at their desks and one at the photocopier.
From there he went on to accounts where terrified staff had barricaded themselves behind a locked door. McDermott blasted it down with his shotgun and then executed two more former work-mates. A third, hidden behind a toppled desk, watched as McDermott pumped shot after shot into the bodies. The court was told he fired 37 shots in all, almost all on target.
When police arrived McDermott was seated in reception surrounded by his weapons. He offered no resistance. He had worked for a year at Edgewater, which handles software development for companies involved in Internet commerce and employs about 250 people in Massachusetts. Born in Plymouth, New Jersey, he served six years in the US navy as an electrician on a nuclear submarine. His former commanding officer told the Boston Globe that McDermott had been an easygoing sailor who fitted in with the rest of the crew.
"A fun guy, not a troublemaker," said Mr Jack Semelsberger, who commanded the USS Narwhal for three of those years.
But his neighbours described him as a loner whose only visitor since his divorce three years ago was a girlfriend.
He seemed to have no interest in making friends with his neighbours at any of the apartment buildings in Rockland, Quincy, or Haverhill where he lived over the last 10 years. He struck some neighbours as a bit bookish and others as a little hostile.
McDermott's answering-machine message strikes an odd note: "Hello, this is Michael's computer. Here I am - brain the size of a planet and what does he have me doing? Reduced to answering the phone. Phones. Oh how I hate phones. They're so depressing." While the scale of the killings in Wakefield is unusual, workplace homicide is not rare in the US. It is the leading cause of fatal occupational injury in the US, with nearly 1,000 murders annually, according to the Federal Bureau of Labor Statistics.