California prosecutors on Tuesday told a San Bernardino County jury they have no doubt that former Marine Christopher Lee killed Erin Corwin, a married woman originally from Oak Ridge with whom he had had an affair.

Corwin, a 19-year-old who was married to a Twentynine Palms Marine at the time, disappeared in June 2014. Her body was found seven weeks later by a rescue team, dumped in the bottom of a remote and abandoned mine shaft in the High Desert. Prosecutors believe Lee lured Corwin into the desert and killed her to hide the affair.

"All the evidence in this case points to one person," Deputy District Attorney Sean Daugherty said during the prosecution's opening statement during the beginning of the trial on Tuesday. The defense opted to delay their opening statement.

Christopher Lee

Daugherty showed audio and visual clips of Lee being interviewed by law enforcement, including a clip where he tells authorities he had a conversation with another person about the best way to dispose of a body. In other clips, Lee, who originally told authorities he barely knew Corwin, admits they had an affair but that he hadn't seen her in more than a month.

Daugherty also showed the jury pictures of a text conversation between Corwin and a friend from her native Tennessee from just before her disappearance. Corwin believed Lee was taking her into the desert for a marriage proposal, according to the texts. Her friend replied back with emoticons of hearts and a diamond ring.

"He told deputies he was coyote hunting that day," Daugherty said of Lee's original statement as to where he was the day Corwin disappeared. "In July, in the middle of the desert, coyote hunting."

A friend of Lee's had taken pictures of the area, which Daugherty also showed to the court. Those pictures were later used to help cave expert Doug Billings map out mine shafts in the area. Billings' map was eventually used to find Corwin's body.

Daugherty also showed another video, taken by a member of the search-and-rescue team that ultimately found Corwin's body, that shows her body crumpled at the bottom of the mine shaft, surrounded by objects such as tires, a propane tank, a homemade torch comprised of a T-shirt and twine, and a Sprite bottle. When her body was examined, investigators found a garrote, made up of two pieces of rebar and a cord, wrapped around her neck.

In Lee's Jeep, officials found a propane tank similar to one found near Corwin's body, Daugherty said, and when Lee was asked about it, he said he was going to use it to blow up a mine shaft. Lee also told investigators he was leaving the Marines on July 6, a little more than a week after Corwin vanished, and planned to move to Alaska with his wife and child. Lee did move to Alaska, and was pulled over by local police who found a garrote similar to the one found wrapped around Corwin's neck when her body was discovered.

Corwin had been told she was pregnant, Daugherty said, and she believed it was Lee's baby.

"He was going to leave, move past all that," Daugherty said. "All the evidence points to one person who planned, prepared, and executed this."

The San Bernardino County District Attorney's Office says opening statements in Lee's trial are set to start in at 1:00 p.m.

In an April 2015 hearing, prosecutors read texts Corwin sent to a friend here in Tennessee before her death. The texts show she had hoped the desert getaway trip would mean an engagement ring. According to her friend’s testimony, Corwin said that Lee had planned the desert trip as a romantic getaway, but he also expected to do some hunting, so he would bring a gun, and he might have to pull it out "for a few minutes."

An arrest warrant filed in California Superior Court in 2014 showed the former marine admitted searching the Internet for advice on how to dispose of a body and .22-caliber cartridge casings and pieces of rebar at the mine shaft where she was found matched those found in his Jeep.

An autopsy revealed Corwin had likely been strangled. Investigators believe her assailant used a homemade garrote, made from rebar and nylon rope, that was found in the mine shaft with her body.

Corwin had believed she was pregnant with Lee's child, though an autopsy was unable to confirm that.