Law enforcement is investigating an Iowa woman’s claim that her late father was a serial killer who murdered dozens of women over the course of three decades.

In a recent conversation with Newsweek, Lucy Studey revealed her late father, Donald Dean Studey, who died in 2013 at 75, killed 50 to 70 women, most of which were sex workers. Studey also claimed her dad buried the bodies around his property in Thurman, Iowa.

“I know where the bodies are buried,” Lucy told the outlet. “He would just tell us we had to go to the well, and I knew what that meant. Every time I went to the well or into the hills, I didn’t think I was coming down. I thought he would kill me because I wouldn’t keep my mouth shut.”

Now, local, state, and federal authorities are looking into Studey’s claims. 

“We are actively investigating this, and who wouldn’t?” Fremont County Sheriff Kevin Aistrope told CNN Affiliate KETV. “We have a scene, but we don’t know whether it’s a crime scene,” the sheriff told KETV. “We don’t have victims, bodies. Nothing.”

Aistrope added, “All we have is a woman came forward and told us a story about bodies in a well. We did bring a couple cadaver dogs. Cadaver dogs looked in there or looked around the area, and they did indicate in the area. I’m not going to say it was right over the well, but they did indicate in the area.”

Meanwhile, Ludey’s older sister Susan alleges Lucy’s accusations are false.

“My father was not the man she makes him out to be. He was strict, but he was a protective parent who loved his children … Strict fathers don’t just turn into serial killers… I’m two years older than Lucy. I think I would know if my father murdered,” Susan told Newsweek.