An 18-year-old man was arrested for the murder of 17-year-old Mateo Castillo during a house party in early November, the Chula Vista Police Department announced.
The U.S. Marshals San Diego Fugitive Task Force arrested 18-year-old James Mumper Jr. of San Diego on Dec. 9 at approximately 4:45 p.m. without incident. According to the Chula Vista Police Department, detectives worked alongside the San Diego County District Attorney’s office to obtain an arrest warrant in the days leading up to his arrest.
Investigators identified Mumper Jr. as the suspect in the Nov. 12 death of Mateo Castillo during a house party in the 900 Block of Rigley Street.
Officers responded to the scene and found a 17-year-old boy with at least one stab wound in the torso and despite lifesaving measures, the boy was pronounced dead at the scene.
Another 17-year-old boy was found unconscious in front of the house with serious injuries to his face and upper body. Witnesses told officers he had been assaulted by several people during a fight. Officers also found another 17-year-old boy about two blocks away at E Palomar Street and Medical Center Court who had stab wounds in his torso.
Both victims were transported to a local hospital and were listed in stable condition.
Mumper Jr. was booked into San Diego County Jail pending charges of Murder and Assault with a deadly weapon. Authorities are still seeking information that would help identify additional suspects and assist with the ongoing investigation.
Anyone with information is asked to contact San Diego County Crime Stoppers at (888) 880-8477 or submit a tip via P3tips (online or mobile application) http://p3tips.com/409 if they wish to remain anonymous.