Fountain, Fla.

The Bay County Sheriff’s office is investigating the death of a 10-year-old girl by her 16-year-old brother.

Deputies were called to the home of Isabella Heffernan on Sunday after she was discovered missing. Her family had last seen her on Saturday night at around 10:00 p.m. when she went to bed at her Fountain home.

Isabella was reported missing Sunday morning shortly before 11:00 a.m.

Bay County Sheriff’s deputies launched a search on the ground in the air.

The body of the girl was found in a large field behind her home.

Deputies arrested 16-year-old Fredrick Matthew Lochridge a short time later.

Investigators have not released a motive for the killing or what specifically led them to arrest the victim’s brother.

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