The gunman, identified as 47-year-old Larry Gene Ashbrook, opened fire with a semi-automatic handgun and rolled a pipe-bomb down the aisle of the Wedgewood Baptist Church during a crowded service on Wednesday night, killing four teenagers and three adults then shooting himself in the head.
He spouted profanities and anti-religious slogans before lighting a cigarette and starting the shooting. The congregation was caught so unawares many people carried on singing before realising the screams and the blood were real.
The pipe-bomb exploded without causing injuries, but the gunman used his 9mm pistol as well as a .380-calibre weapon to pick off his victims one by one. "Everyone thought it was a skit," said 13-year-old Terri Ramirez, who was praying in one of the front pews. "I thought it was a skit, too, and then I saw the girl in front of me get shot."
A further seven people were taken to hospitals with gunshot wounds, including a 14-year-old boy who was shot in the back, the bullet penetrating through and out of his stomach.
More than 150 people were attending the special evening prayer service featuring music by the Dallas-based Christian rock group Forty Days.
With most of the congregation running for cover or cowering beneath their seats, Ashbrook moved inside a pew and shot himself in the temple. Police who rushed to the scene hurriedly evacuated the church in case the gunman was wired with explosives. A bomb-detecting robot found nothing apart from six unused clips for his 9mm weapon.
Within hours of the attack, the Federal Bureau of Investigation searched Ashbrook's house, 10 minutes' drive from the church. He had comprehensively wrecked the place before going on his rampage. Despite finding some journals, the FBI said there was nothing to suggest a possible motive. "I don't know that we'll ever know the answer to why it happened,'' said Robert Garrity, the FBI's special agent in charge.
The series of gun attacks on affluent white American suburbs seem to be endless, once again raising the highly divisive issue of gun control and the socio-cultural factors that influence deranged loners to take out their self-loathing on large groups of strangers as well as themselves.
A 9mm semi-automatic handgun was one of the weapons used by Eric Harris and Dylan Klebold when they terrorised their high school in Littleton, Colorado, in April, killing 12 fellow students and a teacher before committing suicide.
Texas has the highest concentration of gun-ownership of any state, as well as some of the most virulent opposition to gun control.
The state governor and presidential aspirant, George W Bush, said the incident was a "terrible tragedy made worse by the fact that it took place in a house of hope and love", but he made no reference to firearms.
With the Republican- controlled Congress resisting calls for tighter controls on assault weapons and cheap handguns that have no apparent use except to commit crimes, the country has witnessed a particularly bloody summer.
In July, an out-of-pocket day trader in suburban Atlanta opened fire at a brokerage firm, killing 13 people including himself. The following month a white supremacist attacked a Jewish community centre in Los Angeles packed with young children, wounding five people and killing a postman as he made his getaway.
Earlier this week, a Vietnamese man upset over the death of his mother stormed into a hospital in Anaheim, California, and shot three employees dead. At a nearby car parts store, a man opened fire and killed two people. In Fort Worth, yesterday's chat shows and television news stations speculated about the need for metal detectors and other security devices at churches.
Some gun lobbyists said concealed weapons was the answer - enabling armed citizens to kill a would-be murderer before he could shoot anybody himself.