Audrii Cunningham's body found in Trinity River; person of interest ...

Erica Smith/Houston Public Media

The body of a missing 11-year-old Livingston girl who didn't make it to her school bus last Thursday was found in the Trinity River on Tuesday, authorities said.

Audrii Cunningham's disappearance garnered national attention as authorities from around the state searched for her in recent days in the Livingston area, about 70 miles northeast of Houston.

Polk Co. Sheriff

Don Steven McDougal, who had been a person of interest in the case, will be charged with capital murder, the Polk County District Attorney’s office said at a Tuesday afternoon press conference.

Authorities could be seen rushing to an area near a bridge over the Trinity River on Tuesday afternoon before the press conference took place. They immediately surrounded the area with yellow tape and declared it a crime scene. Officials said the Trinity River Authority lowered water levels to help with the search.

Audrii went missing on February 15 when she left for school but failed to get on her bus. A statewide AMBER Alert was subsuquently issued.

McDougal was living in a trailer behind Audrii's home and has admitted to authorities he left the house with Audrii last Thursday, but it remains unclear if he dropped her off at the bus stop or not.

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McDougal was arrested over the weekend on an unrelated charge and is already in custody at the Polk County Jail.

A cause of death was not released, but authorities said they had enough evidence to bring a murder charge and are preparing to file a warrant. The Harris County Medical Examiner will conduct an autopsy.

On Monday, the Polk County Sheriff told reporters McDougal was the last person to see Audrii alive. Authorities also revealed that, while being generally uncooperative with detectives, McDougal had led them to several sites around the lake. Shortly after Audrii's disappearance, a backpack later confirmed to be hers was found near the lake.