The gunman, identified Thursday as Larry Gene Ashbrook of Fort Worth, shouted obscenities as he emptied three ammunition clips from a nine-millimeter, semi-automatic handgun at the gathered congregation.
Ashbrook, who authorities described as chronically unemployed and "very troubled," had six full magazines of ammunition left when he took his own life in a back pew at the church.
According to police, Ashbrook also rolled a pipe bomb down one of the church's aisles. They said the bomb exploded, but caused little damage.
Nearly 150 teenagers were attending the service. Of the seven people killed, three teenagers and three adults died at the church, according to police. Another teen died later at a nearby hospital.
According to the Associated Press, seven others, ranging in age from 12 to 41, were injured in the shooting. Their conditions reportedly improved overnight.
Police searched Ashbrook's house in a Fort Worth suburb. According to officials, Ashbrook's house was in a state of disarray, with holes punched in the walls and furniture upended. Torn photographs and boxes of ammunition littered the floor.
"This has the appearance of being a very troubled man who for whatever reason in his own mind sought to quiet whatever demons were bothering him." FBI agent Bob Garrity told reporters Thursday.
The attack took place at 7 pm CDT, in a middle-class neighborhood on Fort Worth's southwestern edge.
"He walked … into the sanctuary … and was standing back kind of pacing and firing randomly at the people inside," Acting Police Chief Ralph Mendoza told reporters.
According to police, Ashbrook had no previous criminal record, but say his diary writings reveal Ashbrook was "a very emotionally disturbed person."
President Clinton said the shooting showed the nation should do more to safeguard its children.
"Yet again, we have seen a sanctuary violated by gun violence, taking children brimming with faith and promise and hope, before their time," he said. "[W]e know we have to redouble our efforts to protect our children. We know we have to act as if it were our own children being targeted by gun violence. We know that there is nothing we can do to assure that this will never happen; but there is a lot more we can do to assure that it will happen more rarely."
Texas Governor George W. Bush told reporters he did not understand what would motivate Ashbrook to commit such a crime.
"I don't know of a law - a governmental law - that will put love in people's hearts," he said. "It's hard to explain how hatred lurks in somebody's heart to the point where he walks into a church where children and adults were seeking God's guidance and shoots them."
For those who were at the service Wednesday, questions about Ashbrook's motive will continue to linger.
"It's horrible. There's no other way to describe it," Anita Barnard, a mother of one of the teens at the service told The Dallas Morning News Wednesday. She said her son Damon had just seen one of his best friends murdered.
"These were all wonderful kids," she said. "This is going to affect them forever."