A 15-year-old girl from Pennsylvania claimed she accidentally shot her ex-boyfriend in the head with a gun she had stolen while they were lying on his bed — then left him to die alone in his apartment, according to authorities.

Precious Hamilton faces charges of third-degree murder, involuntary manslaughter, possession of a firearm by a minor, and having a firearm without a license in the death of 17-year-old Baseem “Seyven” Baker in Abington Township. Hamilton is being charged as an adult, the Montgomery County District Attorney’s Office reported.

Police responded to a call about an unresponsive person around 5 p.m. Monday at an apartment building located in the 100 block of Old York Road. They discovered Baker deceased from a gunshot wound in his bedroom.

According to a probable cause arrest affidavit, Baker’s mother mentioned she left Baker and Hamilton alone in the apartment to run errands at approximately 2:30 p.m. She returned about two hours later and was surprised to find the door unlocked. After spending 30 minutes on schoolwork, she found her son unresponsive in his bedroom and contacted 911.

The victim’s mother stated that Hamilton had been staying in the apartment with her son over the weekend. Detectives interviewed Baker’s cousin, who was spending time with the victim and Hamilton on Sunday evening. She revealed that Hamilton took out a loaded “cowboy-style” firearm from her bag and showed it to them, according to the complaint.

Hamilton allegedly said she wanted to fire the gun out of Baker’s 11th story bedroom window but he talked her out of it. Instead, she “dry fired” the gun, meaning she pulled the trigger of the weapon while it was unloaded, cops said.  Investigators also found pictures and videos on Baker’s iPad of her holding the weapon, per the complaint.

Surveillance video showed Hamilton leaving the apartment shortly before 3:30 p.m. In an interview with detectives, Hamilton admitted to stealing the gun about two months prior.

Then she told cops her version of events. She said she and Baker began to “play around” in the bed when she decided she did not want to go any further, detectives wrote. She grabbed the gun from underneath the bed.

“Precious stated she produced the firearm in rapid fashion and was surprised when the revolver discharged, instantly striking Baseem and rendering him unresponsive,” cops wrote. “Precious stated Baseem fell off the bed onto the floor.”

She told cops she “panicked” and left the apartment without calling 911 or seeking help, the complaint stated. Hamilton called her mother to pick her up and they went home, the affidavit said.

An autopsy determined the manner of death was homicide, prosecutors said. Cops have yet to recover the firearm, according to the criminal complaint.