Joshua Hilaire, 21, walked into the main police station downtown and turned himself in to detectives.
He was listed Tuesday on the Pima County Jail website as being jailed on a $1 million bond.
Police have connected Hilaire to the killing of 18-year-old Rosaura Hernandez near the 1200 block of S. Craycroft.
According to Sgt. Pete Dugan officers responded to the scene Sunday night.
Details are limited as this story develops. According to Sgt. Pete Dugan, a relative called out of concern for Hernandez, who had been fighting Hilaire, her live-in boyfriend, and asked relatives to pick her up.
Police checked the apartment and found no one home. Two hours later, police responded to a 911 call from the apartment. Police learned that family members had forced entry into the home and found Hernandez injured and unresponsive. She was pronounced dead at the scene with signs of blunt force trauma.
Police say there is a felony arrest warrant for Hilaire for one count of first-degree murder.
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