Authorities on Friday charged a teenager with the slayings of a University of Wisconsin doctor and her husband who were found “lying in a ditch” at a Madison research and recreation area this week.

Khari Sanford, an 18-year-old “known to the family,” was charged Friday with two counts of first-degree intentional homicide for the deaths of Dr. Beth Potter, 52, and Robin Carre, 57, whose bodies were discovered Tuesday, University of Wisconsin Police Chief Kristen Roman said in a Friday video statement. Sanford is currently being held at Dane County Jail.

“We believe that this was not a random act. It was calculated, cold-blooded, and senseless and we will continue to do all we can do to bring justice to Robin and Beth, their family, and their loved ones,” Roman said. He did not release any details about the motive behind the gruesome slayings.

Authorities say that around 6:30 a.m. on Tuesday, a jogger spotted the couple “lying in a ditch” at the UW Arboretum, a 1,200-acre ecological research site with wetlands, forests, and prairies.

Carre was pronounced dead at the scene, and Potter died shortly after arriving at a local hospital, police said. The Dane County Medical Examiner’s Office said Wednesday the husband and wife died from “homicidal related trauma,” but did not provide any additional details.

“Through our police investigation, we reached a point where we are confident that this was not a random act of violence, and this couple was targeted,” UW-Madison police spokesman Marc Lovicott previously told The Daily Beast.

Potter was an associate professor at the university’s Department of Family Medicine and Community Health, the school said. The 52-year-old was also a physician at the Wingra Family Medical Center and Medical Director of Employee Health Services for UW Health.

In a statement, the UW School of Medicine and Public Health said Potter spoke French and Spanish and “approached the practice of family medicine with tremendous compassion, earning the respect of patients and colleagues alike.”

“Words cannot express our grief,” William Schwab, a professor at the school’s Department of Family Medicine and Community Health, said in a statement. “In addition to being a wonderful family physician and highly respected teacher, Beth was a dedicated leader at the Wingra clinic and in our health system. She was wise, warm, and always supportive. There are so many in our department whose lives have been touched by Beth; her loss will weigh heavily within us.”

Carre was an education consultant who ran a business called Carre College Coaching. He was also previously an adjunct history professor at Viterbo University in La Crosse, Wisconsin, and served as a former coaching director at a youth Madison soccer organization, Regent Soccer Club.

“Robin was always there with a shoulder to lean on,” Regent director Julie Bernhardt said in a statement to the Wisconsin State Journal. “Robin was a mentor to many and all-around one of the nicest, kindest, gentlest people I have ever known. This community will miss Robin dearly.”

According to online court records, this is not Sanford’s first criminal offense. Last year, he was arrested for car theft, and in February, he was accepted into a deferred prosecution program.

Roman said that authorities have received “numerous tips,” and urged any residents with information to reach out. The chief also spoke about the investigation’s impact on the community.

“We are in difficult times right now, undoubtedly this unspeakable crime adds to our community’s anxiety, sadness, and feelings of uncertainty,” Roman said. “I know that questions about what happened to Beth and Robin, and why, remain. And I assure you that we will provide as many answers as we can—when we can—as this investigation moves forward.”