A couple in Mississippi has been arrested following an investigation into the mysterious disappearance of the husband’s 81-year-old mother. Authorities discovered a body buried in the backyard of their residence.

The case came to light on Saturday when a concerned family member contacted the Jackson Police Department to report Carol Ryan as missing. The family member mentioned that Ryan was supposed to be residing at a nursing home in Brandon, a city close to Jackson, but had not been in touch for several months.

Jackson Police Chief Tyree Jones shared with reporters on Tuesday night that the investigation steered them toward Ryan’s former residence. The house is currently occupied by her 50-year-old son, John Ryan, and his 48-year-old wife, Samantha Ryan. The police noted that all three had lived there at one point.

Upon obtaining a search warrant, investigators combed the backyard, where cadaver dogs detected signs of human remains, according to Jones.

Using excavators, police unearthed a body wrapped in a tarp, concealed by concrete, buried approximately six to eight feet deep, Jones reported.

Next, a medical examiner will identify the remains and determine a cause and manner of death, according to law enforcement.

The discovered human remains had been buried “long before” Carol Ryan was reported missing, Jones added. The police chief said he did not have an estimate as to how long the body was in the defendants’ back yard.

The missing person investigation will continue until the remains are identified as Carol Ryan’s, authorities said.

Police arrested John Ryan and Samantha Ryan on one count each of desecration of a human corpse. The husband is being detained at the Hinds County Jail on a $100,000 bond while his wife is detained on a $75,000 bond.

The investigation remains ongoing and more charges are possible as investigators uncover more evidence, according to Jones.