A teenager from Arizona has been formally charged with the murder of his former girlfriend, following allegations that he broke into her residence and fatally shot her while she lay in bed.

Emilio Rivera, 18, was apprehended by Avondale Police Department officers on Friday, almost a week after 17-year-old Rhiana Kemplin was discovered with a gunshot wound to her head in the home she shared with her mother. As reported by the local Fox affiliate KSAZ, court documents reveal that Kemplin’s mother informed authorities that prior to finding her daughter, she witnessed a man inside their apartment who pointed a gun at her in the early hours of November 8.

According to the court documents, when Kemplin’s mother encountered the masked individual, whom she identified as Rivera, she observed him attempt to fire the gun twice, hearing a “clicking” sound each time, indicating the weapon failed to discharge. The suspect then fled the scene, prompting her to rush to her daughter’s room where she found Rhiana had been shot in the head.

The documents further detail that the bullet entered Rhiana’s right temple and exited through the left side, also injuring her left hand. She was rushed to the hospital, where she was pronounced brain dead and sadly passed away later that afternoon.

Kemplin’s mother informed investigators that her daughter and Rivera had experienced a rocky relationship, and as a result, he was unwelcome in their apartment.

Police soon questioned Rivera, who lived a six-minute walk from Kemplin’s apartment. Rivera denied that he had a weapon, but he told police that his mother owned a firearm. He also denied having any involvement in her death but he admitted to being at the apartment the night before. Rivera told police that he went to see Kemplin at 11:45 p.m. and they had a fight after he accused her of cheating on him. He said the fight became physical, but he denied hitting her.

Rivera told police that he left Kemplin’s apartment after midnight, but returned to slash the tires on two or three cars in the apartment’s parking lot so Kemplin did not “have the freedom to easily drive around to see other men.” He later returned to slash more tires because he thought the initial couple of vehicles were “not enough.” Rivera admitted to slashing the tires on 14 cars and was booked into jail on 14 counts of criminal damage.

While Rivera sat in jail, police investigated his home and found clothing matching what Kemplin’s mother saw him wearing. They also found a 9 mm Glock 43 handgun in a purse belonging to his mother.

During a court appearance following Rivera’s arrest in connection with Kemplin’s death, authorities stated that ballistics matched the gun found at Rivera’s home to the one allegedly used to kill Kemplin.

Rivera was charged with first-degree murder and attempted second-degree murder. A judge set his bond at $1 million. His next court date is scheduled for Thursday.