A couple from Wisconsin has been charged in a scheme to kill two women using cyanide, with several investigators involved in the case needing hospitalization after exposure to the poison, prosecutors and reports reveal. 

Paul VanDuyne and Andrea Whitaker allegedly concocted poisons in an intricate plan targeting two of VanDuyne’s ex-girlfriends, according to the Wisconsin Justice Department.

It is claimed by prosecutors that VanDuyne broke into a woman’s vehicle at a Costco parking lot in Middleton last month, contaminating her water bottle with cyanide. Upon discovering people near her car suggesting it had been tampered with, she noticed nothing amiss initially, though Fox 47 reported she later found the water’s taste unusual.

Paul VanDuyne and Andrea Whitaker (Dane County Sheriff’s Office)

VanDuyne was arrested Sunday after the hazmat-linked investigations and after authorities caught him allegedly trying to help cover up evidence.

Police had been monitoring VanDuyne but were forced to move quickly when he tried to contact the Rock County woman last weekend. He was arrested and booked Sunday.

While in jail, VanDuyne called Whitaker and asked her to remove items from his house, prosecutors said.  

Agents intercepted her leaving with her belongings. When searching her phone, they found multiple messages between the couple discussing different poisons. Prosecutors believe the pair were planning to murder VanDuyne’s ex-girlfriends with poison.

At least seven state investigators on the case have been hospitalized for possible exposure to the poison, WISN.com reported. 

A Wisconsin couple have been charged in a plot to allegedly kill two women with cyanide. And several investigators tracking the pair were hospitalized after coming into contact with the poison, according to prosecutors and reports. (iStock)

The outlet reported that Dane County Assistant District Attorney William Brown revealed Whitaker’s online history included searches for “Does potassium cyanide cloud water?” and “Sodium cyanide odor, sodium cyanide.”

Searches also included “What does cyanide look like?” and “Cyanide lethal,” he said. 

VanDuyne and Whitaker face charges in Rock County of attempted homicide, aggravated battery, reckless endangerment and stalking — all involving a dangerous weapon.

In Dane County, VanDuyne faces more charges for attempted homicide and stalking, while Whitaker is also accused of helping him and trying to cover it up.

Seven agencies were involved in the investigation, including the Wisconsin Department of Justice’s Division of Criminal Investigation, the Rock County Sheriff’s Office, the Wisconsin State Crime Laboratories and the FBI.