A South Carolina man who local authorities say kept four vulnerable adults captive in a basement and stole thousands of dollars from some of them is now facing additional charges, including murder.

Donnie Ray Birchfield Jr., 35, was charged on Friday, Oct. 17, in connection with the death of Shirley Arnsdorff, 49, the Lancaster Police Department announced in a news release. In addition to murder, he is also being charged with first-degree criminal sexual conduct, according to police.

Arnsdorff died on July 24, and her death was reported the following day, police said. Her death triggered further investigation, leading to Birchfield eventually being charged in August with a litany of offenses, including false imprisonment, aggravated domestic violence, financial fraud and abuse of a vulnerable adult, according to the department.

Lancaster police arrested Birchfield on Aug. 1. As of Oct. 17, he is being held without bond at the Lancaster County Detention Center, according to online court records and the police department.

“My client maintains his innocence in this case and it is important to remember that he is presumed innocent of these allegations,” Ryan Payne, Birchfield's defense attorney, wrote in an email to USA TODAY on Sept. 25. “We look forward to litigating this case in the court system where facts, evidence, and the rule of law matter. We will have no further comment at this time.”