NORTH HIGHLANDS (CBS13) – Detectives have arrested the man suspected in the fatal attack of an 86-year-old woman along the Highlands High School track.

Neven Glen Butler, an 18-year-old North Highlands resident, was already in custody for an alleged unprovoked attack of another elderly woman on Wednesday.

He was identified as a person of interest in the earlier incident at Highlands High School as detectives continued their investigation.

Early Wednesday morning, the 86-year-old woman and a 61-year-old woman were exercising along the track at Highlands High. Deputies say the 61-year-old woman was then attacked by Butler. The other woman, identified as Fusako Petrus, heard the commotion and went to help her friend.

Deputies say Butler then sexually assaulted both women before fatally injuring Petrus.

Later that same day, Butler was arrested after he allegedly attacked a 92-year-old woman along the 2200 block of Northrop Avenue in Sacramento. The woman was injured and was taken to the hospital, while Butler was arrested at the scene.

Butler was originally booked on felony assault and elder abuse charges for the later incident. A charge of murder was added to Butler’s booking after he was connected to the murder of Petrus, detectives say.

Butler is not eligible for bail.