Neighbors said Lockett got out of the crashed car with her throat slashed and ran down the street looking for help.
Around 3 a.m. Friday, Lockett’s mother reported her as missing, investigators said.
Jordan Harp, Lockett's boyfriend, allegedly told her father that he killed her and that Lockett's father would never see her again.
Officers later found Harp, 19, walking nearby and took him into custody. Police said Harp had blood on his hands and clothing.
According to a police affidavit, Harp admitted to investigators that he kidnapped Lockett and stabbed her when she tried to flag down a police officer.
He is being charged with first-degree murder and especially aggravated kidnapping. Harp's bond was set at $1 million.