The remains of a teen who went missing near her Texas home may have been found by law enforcement officials and search volunteers on the 25th anniversary of her disappearance.

Rosemary Diaz, 15, was last seen working at a convenience store near her home in Danevang on November 24, 1990.

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Though there were no obvious signs of a struggle at the store, Diaz's car remained in the store's parking lot and investigators began searching for the El Campo High School student, officials said.

Authorities followed every lead, but no solid evidence ever turned up to indicate what happened to the girl, Texas EquuSearch wrote on their Facebook page.

The volunteer search group said officials with the Wharton County Sheriff's Office asked in November 2015 for help in finding the teen after "investigators learned of some very concerning information relating to Rosemary's disappearance."

Investigators were able to narrow their potential search area to a 60-acre plot of land outside of Danevang that belonged to a one-time suspect.

The search group's director, Tim Miller, and search coordinator, Jack Boggess, met with investigators and on Monday during their first day of their search found bone fragments that were determined to be human, EquuSearch wrote.

Searchers returned to the property the next day and found skeletal remains, clothing and jewelry of an unidentified female, officials wrote.

"This is the ring that was recovered; believed to have belonged to Rosemary Diaz," the Wharton Sheriff's Office wrote on a Facebook post of a gold ring with a pink jewel.

Though forensic anthropologists still have yet to make a positive identification on the remains, officials are confident they found Diaz.

"I can't speculate what happened after she disappeared, other than she is deceased," Sergeant Scott Grosser with the Wharton County Sheriff's Office said at a press conference Wednesday. "She was found in a shallow grave in a remote, wooded area. That is what we expected all along. Exactly how did the abduction happen, there's now ay to know because stores didn't have a lot of video security systems back in those days.

The suspect in the abduction is now deceased, officials said. That person's family still lives on the property and is cooperating with the investigation, officials said.

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The suspect allegedly made "several confessions over time," and the family told officials after the man's death.

"It's very sad that they held on to that information. They could have at least called us to give us peace of mind," Rosemary's sister, Irma Diaz, told KHOU-TV.

"Rosemary Diaz’ family has been on a torturous roller coaster of emotional hope and despair for the last 25 years. Hopefully; the Diaz family may now have some type of peaceful resolve, and some of their questions might be answered," EquuSearch wrote.

The Wharton County Sheriff's Office, the Matagorda County Sheriff's Office, the Texas Rangers and the Texas EquuSearch group aided in the investigation and the search.

"Good job to Wharton Sheriff's Office and all the others involved in bringing this child back to her family," one person wrote on the Sheriff's Office's Facebook page. "It will help them put closer(sic) on 25 years of grief and the unknown. My heart goes out to each of them. May Rosemary finally RIP."

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