Authorities say human remains found in April in rural northwest Missouri are those of a 17-year-old girl who was last seen 10 years ago.

Belton police Lt. Brad Swanson said in a statement Wednesday that the FBI confirmed the remains were those of Kara Kopetsky. The Belton teen was last seen leaving Belton High School in May 2007.

Investigators found her skull in a wooded area south of Belton in April, a day after a mushroom hunter found a different set of remains.

A medical examiner identified the first set of remains as those of 21-year-old Jessica Runions, of Raymore, who disappeared in September 2016.

Runions was last seen at a gathering with 27-year-old Kylr Yust, who has been questioned in Kopetsky's disappearance. He hasn't been charged in either disappearance.