MOORHEAD – An arrest warrant filed in Clay County Seventh District Court against the suspect in connection with the death of a 14-year-old Moorhead girl earlier this week says the two had argued over a recently ended romantic relationship before he stabbed her multiple times.

Isaac Arndt, 18, of Fargo, went to police shortly after 11 p.m. on Monday, Aug. 19, to report an attack by an unknown white male who allegedly followed him and the victim, Jaelyn Walker, in Gooseberry Park, the warrant states. He said Walker fled the area when the attack began and Arndt was taken to a local hospital to receive treatment for a cut on his hand.

Article / Cass County Jail

About 90 minutes later, Walker’s mother filed a missing person report with Moorhead Police and instructed officers to use Snapchat’s location services to search for her daughter in a wooded area near a bike path at the corner of Elm Street and Sixth Avenue.

Officers found Walker’s body at this location. Her back, torso and neck showed “significant sharp force injuries,” the arrest warrant states.

At that point, officers went to the hospital where Arndt was being treated, and he agreed to go with them to the Fargo Police Department. There, he initially retold the story about the unknown assailant, but later admitted that he and Walker “had been in a romantic relationship for several months, but it recently ended.”

Investigators checked Walker’s phone and found that the two had agreed to meet at Gooseberry Park at 7:30 p.m. on Monday.

Arndt told investigators that when Walker refused to reveal the identity of his new girlfriend, he began hitting and kicking him, after which he pulled out a knife and stabbed her.

“The defendant stated that he began hitting the victim and stabbed the victim approximately 13 times. The defendant stated that he fled the scene on his scooter, discarding his phone, backpack and scooter along the way,” the arrest warrant states.

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Arndt told investigators he returned to his Fargo apartment to clean up. A search warrant for the apartment revealed that red-stained socks and a towel were found hidden in a kitchen cabinet and “used toilet paper and toilet paper rolls with red stains were found in the bathroom.”

Police reviewed surveillance video from a home across the street from the wooded area where Walker’s body was found. It showed Arndt approaching the pedestrian bridge into Fargo, first on foot and later on a scooter, and apparently dumping items in the area where Walker’s phone was found.

Arndt told investigators that Walker was dead when he left the scene and that he dragged her body to the river before fleeing.

Preliminary autopsy results from the Ramsey County Medical Examiner showed Walker’s cause of death was homicide by multiple stab wounds. Final autopsy results, including toxicology, are pending.

The complaint states that Arndt is charged with premeditated, non-premeditated, joint murder. The crime carries a maximum sentence of 40 years in prison.

Moorhead police are asking for the public’s help in locating a Samsung Galaxy cell phone with an orange case in connection with the case. According to information provided by the department, the phone may be located anywhere between Second and 10th Avenues and 15th and 23rd Streets South. Anyone with information is asked to call the Red River Regional Dispatch Center at 701-451-7660.