Investigators in LaPorte County now believe they know what caused the deaths of three people found dead last week.

The bodies of 50-year-old Debra Anderson, 68-year-old Donnie Dennis, and 59-year-old Mary Wilson were found in a Michigan City apartment on July 28.

Police have ruled out foul play, but said drug-overdoses and natural causes have not been ruled out.

LaPorte County Coroner Lynn Swanson said Tuesday that drug overdoses are the suspected causes of the deaths, but toxicology test results are pending, reports The Times of Northwest Indiana.

Police are still looking into what happened.