Yarelly Solorio-Rivera, 22, was arrested Wednesday in connection with the Sept. 24 shooting deaths of her 18-year-old sister, Yanelly Solorio-Rivera, and her baby, Celine. Yarelly’s friend, Martin Arroyo-Morales, 26, a gang member, was also arrested, police said. Both are charged with two counts of first degree murder, Fresno Police Chief Paco Balderrama said Thursday. MAN KILLED IN NYE SHOOTING AT POLICE Yarelly Solorio-Rivera, 22, was arrested in connection with the murders of her sister, Yanelly Solorio-Rivera, and her 3-week-old baby, Celine. Authorities in Fresno, California, said the killing stemmed from “jealousy and sibling rivalry.” (Fresno Police Department) “We have the murder weapon, a Smith & Wesson 9mm pistol, and we have a motive – jealousy and sibling rivalry,” he said. “We saw no remorse, no guilt.” Officers were called at approximately 7:20 a.m. on the day of the murders at a home after reports of multiple gunshots being heard inside a bedroom of the home, Fox San Francisco reported. Balderrama said “the scene was traumatic for all the police officers, detectives, EMS personnel and crime scene technicians who responded to the scene.” Yanelly Solorio-Rivera, 18, and her 3-week-old infant daughter, Celine Solorio-Rivera, were killed in September. Yanelly’s older sister, Yarelly Solorio-Rivera, and Martin Arroyo-Morales have been charged in the murders. (Fresno Police Department) When they arrived, police found Yanelly Solorio-Rivera and the child dead. Solorio-Rivera was shot multiple times. Investigators had strong suspicions early on, but didn’t have enough evidence to make an arrest, the chief said. Martin Arroyo-Morales, 26, was charged in the deaths of his girlfriend’s sister and her newborn. (Fresno Police Department) CLICK HERE TO GET THE FOX NEWS APP “This was a sophisticated and well-planned murder,” Balderrama said.