Salt Lake City ? Salt Lake County authorities said Friday that Elizabeth Smart’s cousin appeared to have been the target of an attempted kidnapping last July by the same religious fanatic who is in custody for allegedly abducting Elizabeth.

“I believe we have solid information that can connect the two households and the perpetrators at the two households together,” Salt Lake County Sheriff Aaron Kennard said during an afternoon briefing.

Brian Mitchell, who faces charges of abducting the 15-year-old girl, may have been trying to assemble a group of young wives as part of a new religion he wanted to establish.

Salt Lake City Police Chief Rick Dinse called Mitchell a “self-proclaimed polygamist” and confirmed he was the suspect under investigation in a July 24 incident at the home of Jessica Wright, 15, whose mother is the sister of Elizabeth’s mother.

Mitchell, 49, and his wife, Wanda Barzee, 57, were caught Wednesday with Elizabeth as they walked along a street in the Salt Lake City suburb of Sandy. Formal charges of aggravated kidnapping against the two have been delayed until Monday.

Vicki Cottrell, a friend of Barzee’s, said during a visit Friday Barzee told her Smart was seized to fulfill a revelation from God Mitchell received on Thanksgiving Day 2000. According to the revelation, Mitchell was to take on seven new wives “to bring celestial marriage back on the earth,” said Cottrell, executive director of the National Alliance for the Mentally Ill of Utah.

The new wives had to be under a certain age “because when you get older, you’re more set in your ways,” Cottrell said Barzee told her.

On Friday night, the Smart family celebrated Elizabeth’s return and thanked the community for its support during a giant party in a city park decorated with blue balloons.

They heard from Elizabeth’s mother, Lois Smart, who declared, “I am the luckiest mother in the world. I am overjoyed. Thank you, thank you, thank you.”

She said Elizabeth was doing well — and “doing all the things she should be doing” — such as taking bubble baths and having manicures.

Ed and Lois Smart, parents of Elizabeth Smart, view a poster of Elizabeth at a citywide event celebrating their daughter's return. Elizabeth was found Wednesday in Sandy, Utah. The celebration was Friday in Salt Lake City.

The case now being reopened began at 3 a.m. July 24 when Jessica Wright awoke to the sound of pictures on top of her desk falling to the floor, according to the police report. Looking over at the window above her desk, she saw a thin object — perhaps a knife, or another instrument — sticking through the blinds.

Jessica’s father, Steven, rushed to the room as the girl was leaving, and then called 911. When authorities arrived, they found the bedroom window’s screen had been cut “vertically and horizontally,” the police report said.

Because of the Wrights’ relationship with the Smart family the Salt Lake City police and FBI were called in to investigate. However, the investigation turned up nothing significant and was written off at the time as a probable prank by teenagers who were causing trouble in the neighborhood that night, the sheriff said.

Still, Jessica’s mother expressed concern at the time about the similarity to events the night Elizabeth was taken from her home, especially that a screen cut had been made while the family slept.

This week, after Elizabeth was returned to her family, the sheriff’s office “developed evidence” linking the attempted break-in at the Wright house to the girl’s abduction, Kennard said.

He declined to say whether Elizabeth had offered leads in her interviews with the police, or what the evidence consisted of. He would not address speculation that Mitchell may have wanted to take the cousins as wives.