BLEDSOE COUNTY, TN. (WRCB)-- The woman accused of killing two widowed sisters in Bledsoe County last Tuesday is the daughter-in-law of one of them.

Brenda Brown, 47, is charged with first-degree murder for the death of her mother-in-law, Elizabeth Brown, 82, and Billie Sue Blalock, 79.

She was arrested Wednesday evening, even as Bledsoe County deputies and agents of the Tennessee Bureau of Investigation searched her home on Freda Brown Road, according to Sheriff Jimmy Morris. The property borders her Elizabeth Brown's farm on Mill Dam Road.

"What appears to be the murder weapon was recovered (during the search), Sheriff Morris says.

Morris confirms the weapon is a handgun, but will not reveal what type, or to whom he believes it belongs.

Brown is the caller who alerted 911 dispatchers to the crime last Tuesday.

"She just said that her mother or sister-in-law had been shot or stabbed," Sheriff Morris says.

"She told me she had found them, she was devastated, and she just sort of panicked," former Bledsoe County Executive Ed Frazier says.

The victims are Frazier's first-cousins.

Brown's relationship to the victims, and proximity to the crime scene, made her a suspect immediately, Sheriff Morris concedes.

"In an investigation, the first thing you try to do is rule out the family," he says.

"Because there was no forced entry, it seems like somebody had access some way," Frazier says.

"Miss Brown had a key," Sheriff Morris says.

Frazier and other family members say the widows had changed some of their inheritances.

"By no means do I find that would be a motive," Sheriff Morris says. "All that is still part of the investigation."

Morris confirms that Brown had been convicted of aggravated burglary two years ago, a Class C felony under Tennessee Law. Sentences can run 3 to 15 years, but Brown was on probation, he says.

"That was always a question in my mind," Frazier asks. "Why? "I mean I would have been, if I had done the things they said she did."

Frazier compares his cousins' murders to lambs, slaughtered.

"If I could say to Brenda, I'd say, God help you, if it's true," he says. "God have mercy on you. Nobody it seems, had mercy on them."