Boy, 8, Fatally Shoots Sister, 5, with Gun Belonging to Mom's Convicted Felon Boyfriend: Authorities

The gun was brought into the children's home by a convicted sex offender, authorities said.

An 8-year-old Florida boy fatally shot his 5-year-old sister with a gun belonging to their mother’s boyfriend, who is a convicted sex offender, authorities said.

The siblings and a 4-year-old neighbor, who suffered non-life-threatening injuries, were home alone when the gun was fired, according to the Jacksonville Sheriff’s Department.

Read: Gun Advocate Mom Is Accidentally Shot in the Back by 4-Year-Old: Cops 

Maurice Mobley, 34, was arrested Sunday after turning himself in to deputies. He was charged with being a felon in possession of a firearm, according to Sheriff Mike Williams.

At his initial court appearance Monday, Mobley was ordered held in lieu of $200,000 bail. He did not enter a plea.

He is on Florida’s registered sexual offender list for a 2001 conviction of committing a lewd and lascivious act with a child under the age of 16, according to online records.

The shooting occurred Saturday afternoon, the sheriff said, while the siblings’ mother was out shopping. Williams said details of what happened are still not clear.  

"This is a... tragic, unfortunate, accidental shooting that we have here,” he told reporters. “It’s not very pleasant to go through this investigation at all."

Read: Man Allegedly Shoots Friend While Drunkenly Playing With Gun:  Reports

The eldest child and the injured 4-year-old ran to a neighbor’s home after the gun went off, authorities said.

The mother has not been charged, but the investigation is ongoing, Williams said.

The 4-year-old remains hospitalized and is expected to make a full recovery, Williams said. A counselor has been brought in to treat the 8-year-old, he said.

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