Yemely Rodriguez said she heard the gunshot that killed her pregnant sister and the unborn child Saturday night.
"But I didn't know it was a gunshot," said Rodriguez, 25. She'd never heard a gunshot before.
There was no argument preceding it, she said. Just the shot, in another room of her younger sister's new apartment in Escondido.
Yemely Rodriguez said she ran to find her little sister, Viridiana Rodriguez, in pain, unable to speak and dying.
"She tried to survive," Yemely Rodriguez said. "She tried. She was struggling for her life."
Viridiana Rodriguez was 18 and about four months pregnant, her sister said.
On Sunday, Escondido police said they were looking for a suspect: the slain teenager's boyfriend, Ruben Anthony Cepeda.
Police Lt. Mike Loarie said that though Cepeda, 21, fled the apartment, the investigation led him to believe Cepeda was considering turning himself in.
"He knows he needs to talk to us and give us some details," Loarie said. "He could have somebody bring him to the station. We won't make a big spectacle about it. He can make it easy for himself."
Still, the lieutenant said police considered Cepeda armed and dangerous. Loarie asked that anyone who spots him call 911.
"We've got more eyes out there looking for him than he has friends and family able to hide him," Loarie said.
The shooting happened about 7:30 p.m. Saturday inside the couple's new apartment in the Estancia complex at 725 N. Fig St. in north-central Escondido, police said.
Viridiana Rodriguez, who turned 18 in December, had been shot in the torso, police said. She was taken to nearby Palomar Medical Center, but she and her unborn child died about 8:45 p.m., police said.
The San Diego County medical examiner's office confirmed her death but had not officially released her name as of Sunday.
Standing downstairs from her sister's apartment early Sunday evening, Yemely Rodriguez said she was one of five people inside the apartment when the gun went off. She said she heard her sister cry out and then someone yelled to call 911.
"I didn't know that she got shot," Rodriguez said.
Yemely Rodriguez said she rushed into the other room to help and saw Cepeda frantic and pressing his hands to her sister's stomach.
"He was trying to help her," she said. "He was saying it was an accident."
She said Cepeda hugged his ailing girlfriend.
Confused and shocked, Yemely Rodriguez said, she thought her sister was having a miscarriage.
Yemely Rodriguez said she hurried to her sister and pressed her hands to the wound. She tried to keep her sister awake, she said, but the young woman was unable to speak.
Yemely Rodriguez said the confusion in the apartment was compounded by the fact that Viridiana had just moved in, and no one knew the address when they called 911.
She said that when Cepeda left, she thought he had gone for help. Police say he fled the scene.
"Why did he leave?" Yemely Rodriguez said Sunday as she started to cry. "If it's an accident, why didn't he say (to police) it's an accident? Why did he let her and her baby die the way they did? No one does that. If you love someone and somebody is expecting your baby, you don't do that."
Earlier Saturday, she said, she saw her sister and Cepeda holding hands and behaving affectionately. Yemely Rodriguez said she did not hear any commotion before the gunshot that killed her sister.
"There's no way they were arguing," Yemely Rodriguez said. "Nobody was arguing. To me, I think maybe it was an accident or something because maybe if somebody wants to kill somebody, they are not going to do it in front of other people."
Yemely Rodriguez said Cepeda was from Poway. She said she did not know her sister's boyfriend that well, that they had only dated for a few months. She also said he had had a child with another woman.
Yemely Rodriguez said her sister was well-liked, vivacious and "excited to be a mom."
"She would always make everybody laugh," Rodriguez said. "She never said no to anybody when it came to going out. She was really, really happy. She once told someone to live life (fully) because you only live one time."
The young woman said her family ---- seven siblings ---- was raised in Escondido.
"There were seven of us," Rodriguez said. "Now, there are six."
Loarie said he feared that Cepeda might flee to Mexico ---- a suspicion the officer said was based on the proximity of the border, not on any special tie Cepeda may have there.
Escondido police described Cepeda as 5 feet 8 inches tall, about 150 pounds, with brown eyes and "neat" black hair. He reportedly worked in the construction industry.
Authorities urged that anyone with information about the case call the Escondido Police Department at 760-839-4722, regardless of time of day or day of week.