TAYLORSVILLE, Utah (ABC4) – The two sisters were talking late into the night when there was a knock on the door.

That knock will never be forgotten by Rocio Sifuentes. It changed her life forever.

“It’s been really hard for me, my family and my niece,” said Sifuentes.

Last October, her younger sister Gabriella Sifuentes-Castilla was gunned down in the same home the two sisters shared, and Sifuentes witnessed it.

Sifuentes-Castilla was a popular radio host on a Spanish station. Her on-air name was Gaby Ramos.

Taylorsville police said an ex-boyfriend of Sifuentes-Castilla arrived at the house shortly after 1 a.m. that day in October.

“Muy siloso, he’s a jealous person, a protective person,” recalled Sifuentes.

The alleged murderer is Manuel Burciaga-Perea. Sifuentes-Castilla had broken off their relationship shortly before the shooting.

Sifuentes, the older sister, said the two of them were talking that night when the suspect knocked on the door.

“He was asking for the ring, and he was really violent and I recorded him,” she said. “I called 911 and said he was violent.”

According to Taylorsville police, the call was a hang up. So the dispatcher returned the call only to learn the suspect had left the house.

Sifuentes feared that Burciaga-Perea would return and she asked for a police officer to come to the house in order to file a complaint. But the suspect beat police to the house.

“I was talking on 911,” she said. “He just pulled the gun up or out and he shot my sister in front of me. He shot her like 7-times.”

Sifuentes said her sister’s daughter was in the house but in another room. And fearing she’d be shot too, the sister fled to another room.

“I heard another shot, Sifuentes said. He shot at my sister’s head. It’s horrible to think at that moment. It’s shocking. It’s really hard for me to think about it.”

Sifuentes was actually talking with the dispatcher from 911 when her sister was killed. Taylorsville police arrived but the suspect was long gone.

Wednesday, in part 2 of this story, the long journey to capture the suspect begins.