GUNTOWN, Miss. (AP) — The bodies of a Tennessee mother and her oldest daughter were found behind an alleged kidnapper's house in north Mississippi, the FBI said Monday, and authorities believe the woman's two other daughters are still with the man accused in their abduction.

Jo Ann Bain and her three daughters disappeared April 27. The bodies of Bain and her 14-year-old daughter, Adrienne Bain, were found behind Adam Mayes' house near Guntown, a rural area police have been searching, the FBI said. The bodies were discovered late last week and positively identified.

The FBI said it believed Bain's two other daughters — 12-year-old Alexandria and 8-year-old Kyliyah — were still with Mayes. The agency did not say in a news release why it thought that. Mayes may be using two different aliases, the FBI said.

FBI spokesman Joel Siskovic said no further details were available on the bodies or the search for Mayes and the two girls.

Mayes, a longtime friend of Bain's husband, had stayed over at the family's house to help them pack and load up a U-Haul to drive across the country to Arizona, authorities said. Gary Bain, who was at the house that night, awoke to find his wife, daughters and Mayes gone.

He couldn't reach his wife on her cell phone that day, and reported them missing when the girls didn't get off the school bus.

Mayes was last seen a week ago in Guntown, about 80 miles south of the Bain family's home in Whiteville, Tenn.

Both Gary Bain and Mayes were once married to sisters, Tennessee Bureau of Investigation spokeswoman Kristin Helm said.

Jo Ann Bain's Facebook page showed in the days before the four disappeared she was packing and working on homework. Her last post, dated April 26, said "a good venting always makes you feel better." It didn't say why she was venting.

Jo Ann Bain's aunt said she was waiting for authorities to tell her that her niece and the girls are safe.

"I pray for Jo Ann and the girls to be OK and for them to come home," said Beverly Goodman, who works at Whiteville City Hall.

She said that her niece was not the type of woman to run off with someone.

Goodman expressed frustration that the authorities didn't issue an amber alert sooner. "What would it have hurt to put an Amber Alert out?" Goodman said. "They might have saved a couple of lives."

Linda Kirkland, a family friend and cook at the Country Cafe in Whiteville, said the woman and her daughters were moving to Arizona because two of the girls had asthma.

"Jo Ann and the kids, everyone loves them. We're just hoping to hear that they're safe," she said.

Siskovic, the FBI spokesman, said authorities talked to Mayes early on in the investigation, but he fled when they tried to contact him again.

Mayes also has ties to Arizona, Texas, North Carolina, South Carolina and Florida. He may be using the aliases of Christopher Zachery Wylde or Paco Rodrigass.