THE gunman who killed two New York firefighters after luring them into a trap by setting his own house ablaze left a note saying he wanted to burn down the neighbourhood and "do what I like doing best, killing people".
The chilling words written by William Spengler were made public by police, after it was revealed that the killer had previously been imprisoned over the death of his grandmother.
The conviction for the killing in 1980 meant that Spengler, who took his own life after fatally shooting the firemen on Monday, was not allowed to possess weapons.
After pleading guilty to manslaughter, Spengler served 17 years in jail for beating his 92-year-old grandmother to death with a hammer.
He was released on parole in 1998.
Since then, he had lived in the house in Webster in upstate New York with his mother Arline and sister Cheryl, who is missing after the shootings.
According to officials, Spengler armed himself with three weapons before setting a car and his house on fire on Monday.
When a group of local firemen responded they were met by a hail of gunfire from the 62-year-old, who began shooting at them from higher ground nearby.
Michael Chiapperini, 43, a public information officer at the Webster Police Department who volunteered with the fire service, and Tomaz Kaczowka, a 19-year-old 911 dispatcher, were killed.
Two of their colleagues - Joseph Hofstetter and Theodore Squadron - remain in hospital.
Spengler apparently turned his gun on himself after exchanging fire with an off-duty police officer who arrived at the scene of the suspected ambush.
John Ritter was wounded but released from hospital soon afterwards.
Why Spengler set a trap and attacked the firemen remains a mystery.
Questions were also being raised about how he acquired the three weapons found by his side.
Authorities said they didn't know where he got hold of the guns, but The New York Times reported that there had been a recent spate of gun thefts in the county.
In Webster, Roger Vercruysse, a neighbour, said that the gunman doted on his mother, who died earlier this year - but apparently harboured a deep dislike for his sister.
"He loved his mama to death," Mr Vercruysee told the Associated Press, but he "couldn't stand his sister".