An 18-year-old man was arrested on homicide charges after a 21-year-old was shot and killed inside a home in Washington County overnight. 

Police said the victim and the suspect were both romantically involved with the same woman. Detectives believe the suspect went to his estranged girlfriend's house to confront the victim when he was shot. 

Washington County dispatchers said that first responders were called to a home along Walnut Street in Ellsworth Borough around 11:15 p.m. on Sunday.

Pennsylvania State Police said when troopers arrived at the home, they found the victim, 21-year-old Elijah Johnson of Carnegie, inside. First responders tried to save him, but he was pronounced dead at the scene. 

Police said their investigation led them to 18-year-old Christopher Harper. 

"Early investigation shows Harper going into that residence, locating the female in the middle of the mixture with our victim and then the dispute continues, which leads right to the shooting," said State Police Trooper Rocco Gagliardi.

After the shooting, Gagliardi said Harper fled the scene. Within hours, detectives got a tip and tracked Harper to a home in New Castle, where he was allegedly hiding out. 

"They were able to get Harper into custody and transfer him over to New Castle PSP barracks, where we are waiting to see if we can transfer him back down to Washington County," Gagliardi said. 

Harper is facing several charges, including homicide, burglary, recklessly endangering another person and a firearms violation. 

Gagliardi said the investigation is far from over, however, putting the pieces together and getting an arrest in 12 hours is commendable.