STOCKHOLM, N.Y. (AP) _ Authorities say a buried body has been found during a police search of a missing couple's rural northern New York property.

St. Lawrence County officials tell local media Friday that state police investigators found the human remains in a box lined with concrete and buried on property in the town of Stockholm.

State police have released few other details, but local media report that they started digging up a section of the frozen ground this week.

District Attorney Mary Rain says the case began as a welfare fraud investigation.

A couple in their 80s had lived on the property, but they haven't been heard from in more than a year. Rain says a man who knew the couple is undergoing a mental health evaluation.