April 8 (UPI) — Not long after former delivery driver Tanner Horner was arrested and charged with the kidnapping and murder of 7-year-old Athena Strand of Texas, a woman told police he had sexually assaulted her years ago, when she was 16, an arrest affidavit revealed Wednesday.

Horner has pleaded guilty in Strand’s November 2022 kidnapping and murder. His trial is in the sentencing phase, and prosecutors are seeking the death penalty.

WFAA-TV in Dallas reported Wednesday that an arrest affidavit showed the woman told police that Horner knew her age at the time of the alleged assault. Officials did not prosecute him for that crime as he was facing the death penalty in the Strand case.

Strand went missing from her home in Wise County, Texas, in late November 2022. After a search and Amber Alert, officials found her body about 10 miles from her home. Police said Horner, 31, kidnapped and murdered her after delivering a package to her home and that he confessed and later led police to her body.

Horner pleaded guilty on Tuesday, the first day of his trial, which had been moved from Wise County to Tarrant County. Prosecutors say there is DNA evidence showing sexual assault. They’ve also provided photos that appear to show Strand unharmed in Horner’s truck on the day she disappeared.

Defense attorneys challenging parts of the case have said in court filings that the death penalty is inappropriate because of Horner’s alleged autism diagnosis. They’ve also asked the judge to suppress his confession.

A 12-person jury will make the decision on the death penalty in the case.