Authorities had said they found two bodies Friday at a Guntown, Miss., home of kidnapping suspect, Adam Mayes but the bodies weren't positively identified as Jo Ann Bain, 31, and daughter Adrienne Bain until Monday, CNN reported.
The FBI did not say how Bain and her daughter died.
Still missing are Bain's other daughters, Alexandria, 12, and Kyliyah, 8, whom authorities said they believe are with Mayes, their primary suspect.
The FBI said Mayes may be using an alias, and should be considered armed and dangerous, ABC News reported. Officials said Mayes, described as white and 35 years old, may have altered his and the two girls' appearances.
Roadblocks were set up along Mississippi highways and police were stopping cars and checking trunks. They also asked for the public's help in locating Mayes and the girls.
Mayes was last seen in Mississippi before he allegedly kidnapped Bain and her three daughters after leaving their home in Whitesville, Tenn.
The disappearances were reported by Jo Ann Bain's husband, Gary, April 27. Mayes was questioned in the disappearance, but released by police at that time. When police realized Mayes had given them misleading information, they went to his home to arrest him, but he had vanished.
Union County, Miss., Sheriff Jimmy Edwards said Monday law enforcement officials don't have any leads on Mayes' whereabouts, ABC News reported. An Amber Alert was activated late last week.
"We're not sure that he's in the area. We're not sure that he's left the area," Edwards said. "We don't have anything to confirm either way."
FBI spokesman Joel Siskovic told ABCNews.com law enforcement agencies were "actively looking" in Mississippi, but "there is information to show he has connections to other states. We've got local, state and national law enforcement agents out."
Rick Foster, whose wife was a friend of Jo Ann Bain and whose daughter was a classmate of Adrienne Bain, told CNN Mayes was a Bain family friend and would stay with the family when he traveled from his home in Mississippi to the Whitesville area.
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