BATESVILLE, Miss. – The night a 19-year-old Mississippi woman was burned to death, she and her killer had sex in her car and he thought he had suffocated her before he torched her vehicle with her inside, a prosecutor said Tuesday in an opening statement, presenting his theory of what led to the gruesome slaying.

But a defence attorney said Jessica Chambers told firefighters who found her near her burning car that a man named Eric set her on fire – not the person charged with her murder, Quinton Tellis.

Tellis’ trial began in Batesville, Mississippi, about 80 kilometres south of Memphis, Tennessee. Tellis, 29, could face life in prison without parole if convicted of capital murder.

The horrific circumstances surrounding the former high school cheerleader’s death garnered national attention. Security is tight – the jury is being sequestered and spectators are being screened through metal detectors before entering the courtroom.

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Prosecutor John Champion told jurors that they will see graphic photos of a burned Chambers and they will hear from about 35 witnesses. Chambers had burns on about 93 per cent of her body when she was found along a rural back road on Dec. 6, 2014, the prosecutor said. She died hours later at a Memphis hospital.

He said Tellis repeatedly lied to investigators about spending time with her in the hours before she was found. He also said that Tellis had repeatedly asked Chambers for sex, and she had told him no.

Champion said cellphone records show that Chambers and Tellis – who had met about two weeks before her death and had become friends – were together twice on the day she was burned.

Chambers and Tellis rode around in her car for a while that morning before Chambers dropped off Tellis at his house and she went home to take a nap, the prosecutor said. Chambers then picked up Tellis about 5:30 p.m. and they went to a fast food restaurant, Champion said.

Citing statements Tellis made to investigators, Champion said Tellis and Chambers had sex in her car later that evening. Champion said he believes Tellis suffocated Chambers and thought he had killed her.

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Tellis then drove Chambers’ car with her inside it to the back road, ran to his sister’s house nearby, jumped in his sisters’ car, stopped to pick up gasoline from a shed at his house and torched Chambers’ car and her, Champion said.

“Horrific burns,” Champion said. “Horrific pain.” Tweet This

Chambers was found walking on the road – wearing only underwear in 40 degree temperatures – when a passing motorist spotted her shortly after 8 p.m., Champion said. Her car keys were later found nearby, and they had Tellis’ DNA on them, Champion said.

Authorities have said previously that Chambers was on fire when she was found.

Champion said Tellis first told investigators he only saw Chambers on the morning of her death.

Tellis later acknowledged they were together in the evening, saying he met her to sell her marijuana and had sex with her in her car, Champion said. The prosecutor also said Tellis’ alibi was fabricated.

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Defence attorney Darla Palmer said Tellis is wrongly accused. She said Tellis was buying a pre-paid debit card miles away in Batesville at the time Chambers was burned.

Palmer also said eight first responders who treated Chambers asked her if she knew who did it.

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“She said ‘Eric set me on fire,”‘ Palmer said. “She didn’t say any other name.” Tweet This

In his opening statement, Champion acknowledged that the first responders did hear her say the name “Eric” or “Derek.” Champion said she could have been saying “Tellis,” but the damage done to her throat made it sound different.

Palmer told jurors that Tellis never confessed to the killing.

“He insisted this is not something he would do,” Palmer said.

About 20,000 telephone numbers were analyzed in the investigation. Witnesses will include cellphone data experts, Champion said.

Tellis faces another murder indictment in Louisiana, where he’s accused in the torture death of Meing-Chen Hsiao, a 34-year-old Taiwanese graduate student at the University of Louisiana at Monroe. No trial date has been set in that case.