(CBS/AP) A gunman who left nine bodies scattered across two counties burned down his mother's home with her still inside, killed four relatives on a porch and then targeted strangers before killing himself, authorities said.

Tuesday's shootings in a mostly rural area near the Florida border were believed to be the work of Michael McLendon, who lived with his mother and had once worked at a local metal plant.

The bloodshed began when McLendon burned down his mother's house in Kinston, Coffee County Coroner Robert Preachers said. Authorities found Lisa McLendon's body inside, but they have not determined how she died or whether she was a 10th victim of her son's spree.

McLendon then drove a dozen miles southeast to Samson, in Geneva County, where he took down nine victims, including four members of his family. The rampage ended another 12 miles farther east in Geneva at the metals plant where McLendon had once worked. After a shootout with police, McLendon killed himself.

Kirke Adams, district attorney for Geneva and Dale counties, told CBS' The Early Show that the carnage could have been worse if not for the efforts of local law enforcement.

"They saved probably another 150 people there because he had more ammunition in his car and he was going over there to do some damage," Adams said Wednesday.

Investigators declined to comment on a motive for the shootings, in which at least four other people were injured, including a child. The victims' names have not been released.

"Nobody knew this guy. ... It's still unclear what the motive was. It appears to be something involving a domestic dispute plus a disgruntled employee from his former place of employment," Adams told The Early Show

Five people were killed on the porch in Samson, along with a 74-year-old woman next door, said Adams. Four of the six killed were related to McLendon.

Preachers had said McLendon's victims included his grandparents. But Adams said the 74-year-old victim might have been McLendon's great aunt.

The two unrelated victims on the porch were the wife and 18-month-old child of a Geneva County sheriff's deputy. They had stopped by the home to visit.

"You just can't explain why somebody would do something like this. There's no answers for those questions," Adams said.

McLendon then drove around Samson, shooting out his car window, killing three more people seemingly at random.

"He sprayed bullets through the town," Adams said.

One woman was struck down as she walked out of a gas station. Another man was driving. Another man was shot as he tried to run away.

"In a cowardly act, he shot him in the back," Adams said.

McLendon fired several shots at a Wal-Mart store in Geneva. No one was killed, but it was unclear if anyone was injured.

"There's a lot of people who had close calls," Adams said.

Samson contractor Greg McCullough said he was pumping fuel at the gas station when the gunman roared into the parking lot and slammed on his brakes.

"I first thought it was somebody playing," McCullough said. Then he saw the rifle.

McLendon opened fire, killing the woman who walked outside and wounding McCullough with bullet fragments that struck his truck and the pump. At one point the rifle appeared to jam, then McLendon fired more shots before driving off.

"I'm just in awe that something like this could take place. That someone could do such a thing. It's just shocking," McCullough said.

Police pursued McLendon to Geneva's Reliable Metal Products, where he got out of his car and fired at police with his automatic weapon, wounding Geneva Police Chief Frankie Lindsey. He then walked inside and killed himself.

There had recently been layoffs at the plant, but it was not immediately known if McLendon was among those losing their jobs. A person who answered the phone at the plant said no one could talk about the shooting.

Details about the shooting rampage were slow to emerge, but a caller to CBS affiliate WTVY in Dothan, Ala. reports said that she works at Reliable Metal Products. She said that she her co-workers were crouched in the corner of buildings, trying to protect themselves as the gunman burst through the back door of the business.

A former co-worker of McClendon's, Jerry Hysmith of Samson, said he found him shy, but agreeable.

"He never said anything out of the way to me or anyone," Hysmith told the Dothan Eagle newspaper. "He had a great mother and came from a good family."

Samson Mayor Clay King said he knew the gunman and the victims.

"What I'm focusing on is people here in the town, making sure they feel comfortable," said King, who added the town of about opened a crisis center at the First Baptist Church with counselors available. "I've lived here 44 years and never, never dreamed of this happening."

State Rep. Warren Beck, a Republican whose office is near the Wal-Mart, said his secretary heard gunfire everywhere.

"This is one of the most tragic events ever in Geneva County," he said.Among others injured was a state trooper injured by broken glass after McLendon shot his cruiser seven times. A child of unknown age was taken to Wiregrass Medical Center in Geneva before being flown to another hospital, hospital administrator John Rainey said.

The hospital's staff was ready to treat more injured victims, but their hopes were dashed as death reports trickled in.

"Unfortunately, we were getting the same bad reports as everyone else: Most people were untreatable," Rainey said. "It's something you'd expect in Atlanta or your bigger cities, but in a little town it puts a lot of people in stress. Our nursing staff broke down in tears hearing what was going on and realizing they weren't going to be able to help them."

One of the spots sprayed with bullets was a hardware store in Samson. Yellow tape was strung across glass windows shattered by at least five bullets. A "closed" sign was on the ground outside atop glass shards.

Tommy Boyles, a 76-year-old security guard who works at the same plant where McLendon killed himself, said he and his wife were on the street nearby.

"We could have been caught up in it just as well as anyone else," he said. "That's what scares you: to be an innocent bystander and some nut walks up with a gun."

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