Law enforcement officials have spelled the couple's name Sommerville, though their social media profiles show the spelling as Somerville.
Fred Sommerville was taken into custody following a police pursuit in Pickens County, more than 150 miles away in west Alabama.
"His wife, Lakresha, was in the front seat of the vehicle. She was dead and had been dead for several hours," Limestone County Sheriff Mike Blakely said during a news conference Monday evening.
As of Tuesday morning, Fred Sommerville remained in the Pickens County Jail on charges of abuse of a corpse, attempt to elude, first-degree theft of property and reckless endangerment.
He is expected to be transferred to Limestone County, at which point he will face a charge of first-degree murder for the murder of two or more people.
Blakely said along with the slaying of his estranged wife, Fred Sommerville is also a suspect in the Thursday night killing of Bruce Cosman, 74, of Ardmore, Alabama. The News Courier in Athens reported that Cosman and his wife were inside their home around 7:30 p.m. Thursday when they heard suspicious noises outside.
Cosman went outside to investigate the noises and his wife heard gunshots. According to the newspaper, Cosman was shot multiple times, dying in the yard.
Blakely said Monday that investigators have evidence placing Fred Sommerville at Cosman’s home at the time of the shooting. He did not say what that evidence is.
"There's a lot of things we can't go into at this time because it's still an ongoing investigation," Blakely said.
He said a lot more legwork needs to be done in the case, but he is confident that the killer is in custody. Blakely said one reason he held the news conference was to calm the fears of residents in Ardmore.
"We don't have a murderer running loose up there in Ardmore. We have the person. He is in custody," Blakely said. "We're very confident he is the one that murdered Mr. Bruce."
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The timeline of the killing of Lakresha Sommerville is still not nailed down, Blakely said. He told reporters Monday that the victim’s mother reported her missing, with a possible kidnapping by her estranged husband, late Thursday night.
Fred Sommerville was apprehended in Pickens County, in the town of Aliceville, around 11 a.m. Friday.
Lakresha Sommerville had obviously been dead for hours at that point, the sheriff said.
Blakely said there is no indication Fred Sommerville knew Cosman or his family.
"We have some theories and possibly some evidence that's going to indicate why he wound up at that residence, but we're not prepared to discuss those at this time," Blakely said.
Watch the entire news conference with Limestone County officials below.
It was unclear why Fred Sommerville drove to Pickens County, though investigators said he has an uncle who lives there. Blakely said Sommerville also drove through other areas of Alabama for hours before his capture.
The News Courier reported Fred Sommerville was caught after Aliceville police officers, who had heard reports regarding Lakresha Sommerville's missing vehicle, spotted him downtown and attempted to pull him over.
The officers ultimately fired at the car to stop it, the newspaper reported.
The sheriff said Lakresha Sommerville had filed several complaints against her estranged husband alleging domestic violence and stalking.
"According to the reports we've received so far, she was scared of him," Blakely said.
It was not yet clear exactly where Lakresha Sommerville was slain. According to investigators, she was shot once in the head.
A Facebook page apparently belonging to Fred Sommerville, listed under the name Fila Somerville, shows multiple angry public posts that appeared to be directed at his estranged wife over the past few months.
"All the slander you do towards me only gonna make that number bigger," he wrote less than a week before Lakresha Sommerville was slain. "Get your lawyer, 'cause you gonna pay dearly. Bet that."
Several people have commented on the post since the slaying last week.
"Why, Fred? Why?" Lakresha Sommerville's mother, Cindy Surles, wrote. "Why would you take away the only person that was taking care of your son?"
She wrote that Fred Sommerville did not care about the boy, who, according to Lakresha Sommerville's Facebook page, turned 13 earlier this year.
"All you care about is Fred and if it's not about Fred, then it ain't about nothing," Surles wrote.
On July 2, Fred Sommerville posted that he was in a domestic partnership with Lakresha, who appeared to express surprise at the relationship status. A friend asked Fred if he was OK.
Fred Sommerville wrote that he had some business to take care of.
"This (expletive) the reason y," he wrote, indicating his estranged wife.
Other friends wrote that Lakresha Sommerville was not the source of his problems and urged him to accept that the relationship was over.
On Friday, a woman named Stacey Smith commented on the status, along with several others on the Facebook page, telling those who saw her posts that Fred and Lakresha Sommerville were missing.
"No one has heard from them since yesterday afternoon," Smith wrote. "Their son was left behind and haven’t heard from them! If anyone knows or heard anything please let us know!"
The following day, after news of Lakresha Sommerville's slaying emerged, the comments on Fred Sommerville's page turned to anger and anguish.
"You sorry (expletive), you didn’t have to kill her," one person wrote. "You could’ve thought of your son."
A friend of Lakresha's, April Robison, wrote on a Facebook fundraiser to help Surles fund her daughter's funeral and raise her son, that Lakresha Sommerville was loved and respected by many.
"Kresha was dedicated to her son, her mom, her whole family," Robison wrote. "She could light up a room with her smile. Her laugh was infectious. She will be missed by this entire town. We have lost a truly beautiful soul."
In a December post thanking her friends for birthday wishes, Lakresha Sommerville wrote that she thanked God for life and was looking forward to what the next year of life held for her.
"Just being honest I'm not living my best life yet, but if it's in God's will, I'm on my way," she wrote.
She wrote that she was looking forward to new and exciting things and a drama and stress-free year.
"May Chapter 39 be the best year yet!" she wrote.