A 33-year-old offshore oil worker and registered sex offender pleaded guilty this morning to killing two Louisiana women in separate murders about 13 years apart, KPEL reported.

Brandon Scott Lavergne will spend the rest of his life in prison for slaying University of Louisiana college student Mickey Shunick in May and choking to death 35-year-old Lisa Ann Pate in 1999, according to KATC.

Prosecutors had announced they would seek the death penalty against him, but softened the punishment last week after Lavergne agreed to help authorities locate Shunick's remains. Her badly decomposed body was found near a cemetery on Aug. 7, the Advocate reported.

Lavergne provided prosecutors with a detailed recollection of the murders. The grim details of his confessions were presented in the Lafayette courtroom today.

As Shunick pedaled her bike home late at night in Lafayette on May 19, Lavergne said that he followed close behind in his white GMC truck. He knocked the 21-year-old off the bicycle by ramming her and then convinced or forced her to ride with him, according to prosecutor Keith Stutes. In the cab, Shunick fought to get free. She sprayed Lavergne with Mace and stabbed him with his knife. Lavergne recovered the blade and stabbed her four times, believing that he'd killed her, the Advertiser reported.

Lavergne attempted to get rid of Shunick in an isolated field, but, revived, she again took his knife and stabbed him in the chest. He then shot her and took her lifeless body home before burying it near an Evangeline Parish graveyard.

He threw her bike from a bridge, which was later found, and traveled to a hospital to get his stab wounds patched up.

Lavergne -- who has a previous conviction for aggravated sexual assault -- was arrested on July 5 after his burned out truck was found in Texas and authorities identified it as the one from surveillance footage following behind Shunick.

The Advertiser reported that Lavergne wrote a letter to Shunick's parents. Her father carried it with him, but said he had not read it.

Lavergne pleaded not guilty last month, but felt the desire to come clean after seeing Shunick's relatives on television, his lawyer said.

Stutes also revealed the details of Pate's killing. Pate and Lavergne met at a hotel in Lafayette in 1999 and spent several days together, but he refused to allow her to leave. When he caught her attempting to take his keys and wallet to leave, Lavergne used a plastic bag to smother Pate, KPEL said.

Earlier on HuffPost:

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  • Mickey Shunick

    Authorities in Louisiana are searching for Michaela "Mickey" Shunick, a 22-year-old senior anthropology major at the University of Louisiana, who was last seen on the morning of May 19.

  • Brandon Lavergne

    Brandon Lavergne was arrested on a murder charge in connection with Louisiana college student Mickey Shunick's disappearance.

  • Mickey Shunick

    Mickey Shunick left a friend's home on Ryan Street in Lafayette, Louisiana on the morning of May 19. Shunick was cycling to her home on Governor Miro Drive, a distance of about four miles, when she vanished without a trace, the Lafayette Police Department said.

  • Mickey Shunick

    Ashley Says and Brettly Wilson, friends of Mickey Shunick, give instructions to friends, family and other concerned volunteers at the beginning of a search party for Shunick, a 21-year-old woman last seen on her bicycle leaving Wilson's house on Ryan Street, pictured, in the early overnight hours Saturday in Lafayette. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Leslie Westbrook, The Advertiser</a>)

  • Mickey Shunick

    Friends, family and other concerned volunteers begin a search for Mickey Shunick, a 21-year-old woman last seen on her bicycle leaving a home on Ryan street in the early overnight hours Saturday in Lafayette. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Leslie Westbrook, The Advertiser</a>)

  • Mickey Shunick

    A private donor is offering a $10,000 reward for any information leading to Mickey Shunick's whereabouts, no questions asked.

  • Mickey Shunick

    Volunteer and friend Ashley Says comforts Charlie Shunick, Mickey Shunick's sister, on Monday, Mickey's 22nd birthday. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Megan Wyatt, The Advertiser</a>)

  • Mickey Shunick

    Mickey Shunick is described as a white female, 5'1" tall and approximately 115 lbs. She has shoulder-length blonde hair and blue eyes. Shunick has a small tattoo of a bicycle on her right outer ankle and a nose ring on her left nostril. She was last seen wearing a pastel striped shirt, light wash denim skinny jeans, and silver ankle boots. She was carrying a light brown leather backpack, a black and yellow Vera Bradley wallet, a black Verizon slider phone and a small pink container of mace.

  • Mickey Shunick

    Mickey Shunick's siblings, Charlie and Zack Shunick, investigate possible routes Mickey traveled on her bicycle early Saturday morning. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Megan Wyatt, The Advertiser</a>)

  • Mickey Shunick

    Friends, family and other concerned volunteers begin a search for Mickey Shunick, a 21-year-old woman last seen on her bicycle leaving a home on Ryan street in the early overnight hours Saturday in Lafayette. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Leslie Westbrook, The Advertiser</a>)

  • Mickey Shunick

    Friends, family and other concerned volunteers begin a search for Mickey Shunick, a 21-year-old woman last seen on her bicycle leaving a home on Ryan street in the early overnight hours Saturday in Lafayette. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Leslie Westbrook, The Advertiser</a>)

  • Mickey Shunick

    Mickey Shunick's siblings, Charlie and Zack Shunick, investigate possible routes that Mickey traveled on her bicycle early Saturday morning. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Megan Wyatt, The Advertiser</a>)

  • Mickey Shunick

    Ashley Says, left, and Lindsay Beggs, friends of Mickey Schunick, post flyers Sunday morning during a search Schunick, a 21-year-old woman last seen on her bicycle leaving a home on Ryan street in the early overnight hours Saturday in Lafayette. (<a href="http://www.theadvertiser.com/apps/pbcs.dll/article?AID=2012205220313" target="_hplink">Leslie Westbrook, The Advertiser</a>)

  • Mickey Shunick

    Police in the Lafayette area encourage anyone with any information regarding Mickey Shunick's whereabouts to contact them at 337-291-8600. Tipsters can also send an email to findmickeyshunick@yahoo.com.

  • Ashley Says, Kim Schifino and Mickey Shunick

  • Mickey Shunick with her brother Zack, her sister, Charlene, her father Mckey and her mom Nancy.

  • Mickey Shunick and her sister Charlene

  • Mickey Shunick and her sister Charlene

  • Mickey Shunick and Raven Talley

  • Ashley Prado, Marion Trosclair and Mickey Shunick