Updated

The wife of an Alabama minister missing since March sold her wedding ring at a pawnshop on the day she disappeared, police said Thursday.

Mary Byrne "Beth" Smith, 30, is seen on surveillance video from a Bossier City, La., pawnshop hocking her wedding ring the morning she was reported missing, Bossier City police said.

The store security camera shows Smith wearing a purple shirt and exiting the shop at 11:36 a.m. on March 24, the same day she disappeared from Living Proof Live, a women's conference she was attending with her friend Jenny Gipson at the Bossier City CenturyTel Center.

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The video reiterates investigators' belief that Smith, the wife of Rev. Jason Smith of Summerdale, Ala., left on her own free will, Bossier Police Chief Mike Halphen said in a statement. Smith does not face criminal charges, but police would still like to locate her.

In April, police outlined a chain of events that led them to believe that the kindergarten teacher might have disappeared on her own.

In December, Smith told staff at Elsanor Elementary School in Robertsdale, Ala., where she taught kindergarten, that she had divorced her husband, the leader of the First Baptist Church in Summerdale, when in fact she hadn't, Halphen said.

Also, Smith had a suspicious fall and asked teachers where she could find prescription pain medication and reported her purse stolen, but it was later found -- containing empty prescription bottles -- in her desk at school, Halphen said.

"The principal felt like she was under the influence of some type of either alcohol or drugs," Halphen said. "She was drug tested recently and it came back positive."

Following the Feb. 2 drug test, the school decided to dismiss Smith, effective at the end of the school year.

"With all this information, as you can see, it's very easy to see that there is a great possibility she decided to leave on her own and maybe planned this out by coming to the Bossier City area and then leaving," Halphen said.

Mary Byrne Smith checked into the Shreveport Courtyard Marriott Financial Plaza on March 23 with Gipson. The pair planned to attend the conference, a two-day women's religious event led by evangelist Beth Moore.

The following day, the pair returned to the CenturyTel Center in Bossier City to hear Moore speak on living a life of spiritual victory by growing in one's faith in God.

"At 11 o'clock that day, she told her companion that she was going to go to the concession stand and use the restroom, and it was the last time that Mrs. Smith was seen," Halphen said.

Gipson reported Smith missing that afternoon.

At the time of the event, some 30 police officers were stationed in the arena to help control the approximately 14,000 people who attended the conference.

"We felt like if she were under duress, if somebody tried to force her somewhere, that it would have been very easy to holler help with 14,000 people standing around you," Halphen said.

Bossier City police used dogs, helicopters, airplanes and boats to search the area in the days following her disappearance.

Smith, who goes by the name Beth, is described as a 5-foot-3-inch white woman weighing 100 pounds. Both her hair and her eyes are brown. She has a sun tattoo on her back shoulder.

Anyone with information on her whereabouts is asked to call the Bossier City Police Department at 318-741-8605.

The case remains open, Halphen said.