DALTON, Ga. -- An autopsy is scheduled Saturday for a 78-year-old man accused of setting off an explosion at a Dalton law office.

Investigators said Lloyd Cantrell, 78, set off the explosion that blew out the windows at McCamy, Phillips, Tuggle & Fordham around 10 a.m. Friday. Cantrell died at the scene. Four others were hurt.

Cantrell's body was taken to the GBI crime lab in DeKalb County for the autopsy.

The bombing came after a bitter family dispute erupted over property in north Georgia. The explosion blew out windows of the two-story, colonial-style house where attorneys worked, and some in the small blue-collar town of 30,000 felt vibrations from more than a block away.

At a press conference late Friday afternoon, Georgia Bureau of Investigation spokesman John Bankhead said a search of Cantrell's truck found canisters of natural and propane gas as well as gasoline. Bankhead said agents are "very carefully" searching the vehicle for more evidence.

Cantrell's neighbors were shocked after the explosion.

"I considered him like an old hermit," one neighbor said. "It (the explosion) blew my mind."

Cantrell was a man known around town for wearing bib overalls and carrying a small Chihuahua. Over the years, Cantrell amassed several parcels of land in the area, and gave some of the property to his son.

His son had grown fearful of his father, though, and filed a lawsuit seeking to keep his dad off the property the son had been given, claiming the elder man stole tools, kicked down a door and was suicidal.

Authorities said it was too early to talk about a motive in the case, but the dispute between the father and son was well-documented in court records.

"Essentially, what we've got here is not an act of terrorism," said Scott Sweetow, an agent with the Bureau of Alcohol, Tobacco, Firearms and Explosives. "It is a depraved individual, by all accounts, who decided to launch what ended up being a suicide attack."

The firm housed the office for Samuel L. Sanders, who represented Lloyd Cantrell's son in a bitter legal dispute that dated back at least two years. A police spokesman said he didn't know whether Sanders was in the office at the time of the explosion.

Lloyd Cantrell's attorney, David Blackburn, said Cantrell's son, Bruce, filed a lawsuit seeking to block his father from the land, in part claiming that his dad carried a pistol with him and threatened to kill himself.

"He has repeatedly said that 'The only thing that would keep me off the property is to be put in jail,"' according to a complaint filed by Bruce Cantrell's attorney in 2006.

Several attempts to reach Bruce Cantrell Friday were unsuccessful.

The case was set to go trial in August, but it was delayed.

"I know he got frustrated because it took so long," Blackburn said of his client. He described the family as "abysmally dysfunctional."

Cantrell's daughter told CBS 46's Renee Starzyk that she was in the courthouse when the explosion happened. She said she didn't know for hours whether her father was dead or alive.

Police said earlier Friday, Cantrell was involved in a meeting about a 2006 civil lawsuit at the office before the blast. An officer saw someone get out of a sport utility vehicle and run behind the building, then something exploded, investigators said.

Authorities think Cantrell threw the explosive through a front window or door. As of late Friday, they hadn't identified the nature of the explosive.

Attorney Robert Smalley, a lawyer at the firm, left 15 to 20 minutes before the blast but turned back when he received phone calls about it. He said those injured were his assistant, Teresa Stinnett, attorney Jim Phillips and two clients. Phillips was taken to the burn center. Hospital spokeswoman Anne Cordeiro said he was in critical condition.

"We'll take today with our families and try to regroup," he said. "Our thoughts right now are with the injured and their families."

He said Stinnett has a shoulder injury but is going to be OK. Smalley said he was able to visit with Phillips after the explosion.

A block and a half from the blast site, bank executive Wayne Russell heard and felt the explosion.

"It sounded like a transformer that's blown," said Russell, 53, executive vice president of Omni National Bank. "We could actually feel a sort of rocking motion from the explosion."

The eight-lawyer firm was founded in 1932 and specializes in personal injury and wrongful death cases, according to its Web site.

Police cordoned off the block and shut down a post office near the law firm. Students at an elementary school across the street were evacuated to a nearby church.

Dalton is located about 25 miles southeast of Chattanooga, Tenn.