CNN
 — 

The body of Audrii Cunningham, an 11-year-old girl who disappeared while on her way to school in Texas, was found Tuesday in the Trinity River, according to Polk County Sheriff Byron Lyons.

“Audrii’s body was located at the Trinity River under US Highway 59,” Lyons told reporters at a Tuesday news conference. He later said her body had been taken to the medical examiner’s office in Harris County and officials were awaiting information on her cause of death.

Polk County District Attorney Shelly Sitton said they are in the process of preparing arrest warrants for Don Steven McDougal, 42, adding they believe a capital murder charge will be appropriate.

“Based on all of the evidence that law enforcement has collected, they are in the process of preparing the appropriate arrest warrants,” Sitton said. “At this time, we believe the appropriate arrest warrant is going to be for capital murder in the death of Audrii Cunningham. He is still in jail under an unrelated felony charge.”

When asked by reporters how Audrii was killed, Sitton said, “I cannot speak to that.”

McDougal, a friend of Audrii’s father, gave investigators a list of places he had been to, but didn’t divulge where her body was, according to the sheriff. Lyons added authorities also used cell phone data and video to help find her remains.

McDougal was already in custody after he was arrested Friday night on unrelated aggravated assault charges, according to the sheriff’s office.

McDougal has a lengthy criminal past with convictions for violent crimes and another for enticing a child, according to court records in several Texas counties.

In 2007, he was convicted of enticing a child in Brazoria County, Texas. Court records show he pleaded no contest and was sentenced to two years in prison, but given credit for 527 days. Online records in Brazoria County do not provide details on the specific allegations in that case.

He was also convicted in 2010 and 2019 for aggravated assault with a deadly weapon.

The victim in the first case, which led to a four-year prison sentence, told CNN on Tuesday that McDougal, his former coworker, attacked him after being thrown out of his house.

“He showed up with some other friends that I had,” Elic Bryan said. “We ended up throwing him out of the house and he came back with a knife.”

McDougal began stabbing the door before coming back inside, Bryan said.

“He came at me with the knife, and I had my shotgun, and I hit him in the face with it,” Bryan said. “I had no idea he was that kind of person.”

CNN is working to determine whether McDougal has legal representation and has also reached out to his family for comment.

McDougal had joined in the search efforts for the missing girl, the sheriff told CNN earlier Tuesday.

“Some of the witnesses have even said that he was in the community and knocking on doors … asking have they seen her,” the sheriff told CNN.

“To me, it simply tells me is that he’s trying to give the appearances that he has no play or he’s not at fault in her disappearance and that (he’s) part of the concerned parties who were trying to locate her.”

McDougal apparently took to social media last week to state his innocence.

A comment of “I’m not guilty,” from a Facebook account appearing to belong to McDougal was added under a post on the Facebook page “True Crime Society” the day after Audrii Cunningham was reported missing.

“I was there and was questioned. I am not running or hiding,” McDougal wrote before commenting again and saying, “I have done everything I can to help find her. I have done nothing wrong.”

Another comment reads: “I am the one that went and knocked on the houses by the bus stop to get video footage.”

Most of the posts were made early Friday morning.

Law enforcement officials didn’t immediately respond to CNN’s request for comment on the posts.

McDougal lives in a trailer on the family’s property and sometimes took Audrii to the bus stop, the sheriff said.

The family’s home is near Lake Livingston – “one of the largest reservoirs in the state, with 83,000 surface acres,” according to Texas Parks & Wildlife.

Around 7 a.m. Thursday, McDougal and Audrii left the house for the bus stop, authorities said. That was the last time Audrii’s family saw her. She never made it onto the school bus or to school that day.

Her backpack was found near a dam on the lake Friday, about 5 miles from where her body was discovered Tuesday.

The sheriff said there were no signs of struggle where the bag was located.

CNN’s Steve Almasy, Raja Razek, Andy Rose, Jillian Sykes and Carroll Alvarado contributed to this report.