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DETROIT, Michigan (CNN/In Session) -- A jury rejected an 18-year-old's claim that he acted in self-defense, finding him guilty of murder in the gory stabbing, beheading and torching of a Michigan man.
Jean Pierre Olewicz says he feared for his life when he killed Daniel Sorenson.
The jury of eight men and four women deliberated for more than 10 hours over two days before finding Jean Pierre Orlewicz guilty of first-degree murder, felony murder and mutilation.
Jurors did not look at anyone as they filed into the courtroom. The defendant's family remained stoic, but the father of victim Daniel Sorenson broke into sobs. Watch as the verdict is read »
During the trial, some of the most gruesome details of Sorenson's slaying came from the youthful-looking defendant's own lips.
Prosecutors called Sorenson's slaying a "thrill killing." They alleged that Orlewicz was excited by the prospect of killing someone and getting away with it.
Orlewicz, of Canton, Michigan, took the stand and admitted that he killed Sorenson, 26, but insisted that it was in self-defense. He admitted stabbing Sorenson 13 times after an extortion plan went awry and Sorenson threatened his life.
"There was not a murder," Orlewicz testified.
On November 7, Orlewicz said, he, Alexander Letkemann and Sorenson arrived at his grandfather's house in Canton, Michigan, with the intent of robbing Adam Duwe, who had just inherited $40,000. But Orlewicz said he felt "icky" about the plan and was going to pretend Duwe couldn't make it. That's when Sorenson's temper flared, Orlewicz testified.
Orlewicz said Sorenson took out a gun and threatened to kill him.
"You think this is a game?" Orlewicz recalled Sorenson screaming. "I'm going to drop you to your knees and blow your frigging brains out."
Orlewicz said Sorenson began waiving the gun around, so he grabbed a knife from a tool bench and stabbed him from behind.
As the two fought, Orlewicz said, the gun dropped from Sorenson's hand. Sorenson scrambled to find the gun, Orlewicz said, and the two continued to struggle. "I kept trying to stab him and get leverage in the fight," Orlewicz said. "I was stabbing him in the back."
During his testimony Orlewicz also admitted that after Sorenson died, he used a hacksaw to decapitate him. Orlewicz said he threw Sorenson's torso into a field and set it on fire. The defendant said he took a blowtorch to Sorenson's hands to cover up fingerprints.
Orlewicz told the jury he feared that Sorenson was tied to the Mafia and that his family would come after him.
He said his actions after the death were all out of panic.
Orlewicz corroborated Letkemann's testimony that Letkemann stood by and did nothing as Orlewicz stabbed Sorenson.
Letkemann, 18, pleaded guilty to second-degree murder April 1. He will face 20 to 30 years in prison in exchange for his testimony against Orlewicz.
Orlewicz denied Letkemann's assertions that after the killing, he played with Sorenson's head like a puppet.
"That's someone else's imagination," he said.
Prosecutors paraded several witnesses in front of the jury who claimed Orlewicz had said that he wanted to kill someone and that he owned a gun. Orlewicz denied the claims, including one man's testimony that he watched Orlewicz take out the gun, put one bullet in the chamber and play Russian roulette.
Alex Mullins, 17, told police he was supposed to be the lookout on November 6 when Orlewicz planned to kill Sorenson. When the plan was postponed until the next day, Mullins decided he didn't want to be involved, he testified.
Orlewicz had spoken for weeks about wanting to kill Sorenson, Mullins added. "He wanted to stab Dan," Mullins said. "He wanted to bag him up in a tarp, hang him upside down from a tree, burning. He said he wanted to cut his head off."
Assistant Wayne County Prosecutor Robert Moran told jurors in his closing arguments that Orlewicz's self-defense theory was bogus and that Orlewicz's testimony about an extortion plan was a cover-up for a gruesome calculated murder.
"There was no plan to extort money," Moran said. "That was the ruse to get the victim there."
Defense Attorney Joseph Niskar asked the jury in his closing arguments to consider the "fear factor" that came into play when Sorenson, who was twice Orlewicz's size, threatened his client with a gun. Niskar argued that if Orlewicz had plotted the murder, he wouldn't have brought a "knife to a gunfight" but instead a stronger weapon to combat the gun he knew Sorenson had.
Moran told the jury that the only possible way for them to find Orlewicz not guilty was to be believe his testimony rather than every single other person who took the stand.
For someone who feared for his life, Orlewicz was fairly calm about the gruesome actions he took against Sorenson, Moran said.
"Where was his emotion when he testified?" Moran asked. "Where was his emotion when he testified that he had to kill Mr. Sorensen? When he had to cut off his head? He testified like he was ordering a pizza. A typical day. That's him. That's cold."
He recounted the gory details of how Orlewicz admitted to decapitating Sorenson and covering up the crime, saying: "We'll never forget it."
"Thanks, Mr. Orlewicz," Moran said. E-mail to a friend
This story was written by CNN's Mallory Simon. In Session correspondent Jean Casarez contributed, reporting from Detroit, Michigan