Dena Marie Anderson

In the small community of Big Lake Township, Minnesota, Dena Marie Anderson was known as a dedicated stay-at-home mom. At 34 years old, her life revolved around her husband, Mark, and their three young children: 8-year-old Jake, 5-year-old Cassie, and 3-year-old Melanie. The day before Thanksgiving in 1996 was the last time her family would see her, marking the beginning of a mystery that has now spanned decades.

On the morning of Wednesday, November 27, 1996, Mark Anderson left for his construction job, having last seen his wife around 5 a.m. The couple spoke again by phone that afternoon. Later that day, investigators from the Minnesota Bureau of Criminal Apprehension (BCA) reported that Dena, a White female, was seen with a man they described as a "boyfriend" at the Lake Pine Motel in Big Lake. The last confirmed sighting of Dena was around 11 p.m. at the Broadway Bar and Pizza in Elk River, about nine miles from her home. She was wearing a long black leather coat, blue jeans, and brown leather shoes. When she failed to return to her family, her husband reported her missing. “It’s unusual … that someone would leave and not say anything to her husband and children,” Mark Anderson later told the Star Tribune. “There’s just no way she just took off. I don’t believe that for a minute and neither do her mom and dad.”

The day after her disappearance, Thanksgiving Day, Dena's car was found still parked in the lot of the Broadway Bar and Pizza. The same day, a troubling discovery was made more than 45 miles away when a motorist found Dena’s purse discarded along Interstate 35, just north of Pine City. “What woman would throw her purse into a ditch along Highway 35 that far from home,” her husband questioned. Despite extensive searches, there was no sign of Dena.

As months passed with no answers, the case grew colder. In February 1997, the Sherburne County Sheriff's Office announced a $5,000 reward for information that could lead to an arrest, but no one came forward. The brutal Minnesota winter of 1996-1997, which was so harsh that 40 counties were declared disaster areas, eventually gave way to spring. On May 18, 1997, nearly six months after Dena vanished, a resident taking a walk with friends discovered a body in a wooded area in Mission Creek Township, near Highway 61. The remains were fully clothed and found about four miles from where her purse had been located.

Due to significant decomposition, the body was not immediately identifiable. The Ramsey County medical examiner used dental records to confirm the remains were those of Dena Marie Anderson. Authorities believe her body had been there since shortly after her disappearance, concealed for months under the heavy winter snow. “The body had probably been there for some time, it was not visible from the road and probably had been covered by snow most of the winter,” Pine County Sheriff Steve Haavisto stated in 1997. Dena's funeral was held on May 21, 1997, and she was buried at Orono Cemetery in Elk River.

The investigation into Dena’s death has been a joint effort between the Sherburne County and Pine County sheriff’s offices, with the Minnesota BCA classifying the case as a homicide. However, details surrounding her cause of death have never been publicly released, believed to be undetermined due to the condition of her remains. Though investigators initially stated no foul play was suspected in her disappearance, the case has remained an active homicide investigation. In 2012, authorities officially reopened the cold case, hoping new eyes and technology could shed light on the mystery.

As of October 2026, Dena Anderson’s killing remains unsolved. No one has ever been charged in connection with her death, and investigators with the Sherburne County Sheriff's Office have stated that no one has been ruled out as a suspect. The questions of who killed Dena and why continue to haunt her loved ones and the investigators dedicated to finding answers.

Authorities urge anyone with information, no matter how insignificant it may seem, to come forward. Tips can be directed to the Minnesota Bureau of Criminal Apprehension at 877-996-6222, the Sherburne County Sheriff’s Office at 763-765-3500, or the Pine County Sheriff’s Office at 320-629-8380.