JACKSONVILLE, Fla. -- A 17-year-old accused of murdering a 13-month-old pleaded guilty in a Duval County courtroom Monday morning.

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Javarris Lane pleaded guilty to charges of second degree murder, aggravated child abuse and sexual battery on a child under 12, according to a news release from the State Attorney's Office.

Lane pleaded guilty just before jury selection was scheduled to begin for his trial.

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Lane was watching 13-month-old Alexandria Williams in September 2011, the release said, at his home on West First Street. Williams was a friend of the family.

The release said evidence showed Lane shot the crying toddler, hit her head multiple times on a dresser and sexually abused the girl. Williams died days later due to her injuries.

Assistant State Attorney Janeen Mira said, "I'm relieved the family does not have to go through a trial and hear the facts about what happened to little Alexandria."

Lane faces life in prison. He is scheduled to be sentenced October 15, 2012.