BALTIMORE (WJZ) — Days after workers discovered a woman’s body near Port Discovery, police say they have her killer in custody.

A teenager has now turned himself in, confessing to rape and murder.

Police say the 18-year-old confessed to raping and strangling a woman to death, then sexually assaulting her body. But why he did it, they can’t say.

Tucked down a side street near Port Discovery Children’s Museum, police say they found a gruesome discovery.

Last Wednesday, workers found a woman raped and strangled to death. Police say her killer is 18-year-old James Arthur House.

“His confession was complete. Very sad,” said Baltimore City Police Commissioner Kevin Davis.

Before 35-year-old Jessica Gibson’s death was even ruled a crime, police started releasing surveillance videos, taken inside a downtown convenience store. They show House in the check-out line.

Officers say the teenager saw those videos on social media and turned himself in.

Police say this wasn’t a random crime. The victim and her killer did know each other, but what exactly their relationship was, officers can’t say.

“She had some of life’s issues going on. Of course, that doesn’t make her any less of a victim,” says T.J. Smith, with Baltimore City Police.

Gibson was homeless at the time, staying in a shelter across the street from where House allegedly abandoned her body behind a pile of pallets on East Coast Greenway.

House is now accused of murder and rapes occurring both before and after her death.

“Our victim was sexually assaulted in a most brutal way,” says Commissioner Davis.

These were horrific crimes, police say House copped to — the first arrest on his adult rap sheet, landing him a dozen charges. Though, what led up to it all is still a mystery.

Police say House is not homeless. But how he knew Gibson is still unclear. They say the victim was a mother of four.

Police first investigated Gibson’s death as suspicious before the Medical Examiner ruled it a homicide late last week.

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