A Colorado teenager is accused of gunning down his 15-year-old ex-girlfriend, as her terrified baby brother listened to the slaughter from a nearby bedroom.

Jovanni Sirio-Cardona, 16, allegedly shot Lily Silva-Lopez seven times mere feet from her little brother on June 16 in Greeley, according to a press release from the Weld County District Attorney's Office.

Sirio-Cardona and the victim had dated for about six months before she ended the relationship four weeks prior.

At about 3:45 p.m., Sirio-Cardona crawled through Silva-Lopez's bedroom window as she yelled for her little brother, who was watching TV in another room, to run for his life, according to an affidavit obtained by Denver7.com.

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Colorado teen stands in between trees wearing a jean jacket.

Colorado high schooler Lily Silva-Lopez, 15, was allegedly fatally shot by her ex-boyfriend, Jovanni Sirio-Cardona June 16, 2023. (Adamson Life Celebration)

The boy hid in a bedroom and tried to dial 911 when he heard the gunshots, he told detectives. He peered into the hallway and saw his sister on the ground and Sirio-Cardona, blood dripping from his nose, standing over her lifeless body. 

Sirio-Cardona was clutching a black handgun with a green scope, according to court documents cited by the local news station.

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The boy begged his sister's alleged killer not to shoot him. Sirio-Cardona demanded the 13-year-old's cellphone, so he couldn't call the police, and dragged the girl's body into her bedroom before fleeing.

The Northridge High School junior was pronounced dead at the scene. A neighbor told FOX31.com that one bullet tore through his trailer narrowly missing him.

A brown trailer with white car in driveway

The trailer, left, where Lily Silva-Lopez, 15, lived with her family when she was fatally shot June 16. Her neighbor told FOX31 that a bullet tore through his trailer wall, right, and narrowly missed him. (FOX31)

Sirio-Cardona's controlling and abusive behavior had allegedly escalated since their split. 

When Silva-Lopez told her beau it was over a month prior to her murder, he allegedly put the barrel of a gun into her mouth and told her, "She wasn't going to break up with him, and she needed to tell him she loved him." 

The young girl confided in a family member, who relayed the account to police after her death, according to court records cited by Denver7.com. 

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Six days before the shooting, Sirio-Cardona allegedly punched her in the face and injured her arm, according to a domestic violence complaint.

After the alleged murder, Sirio-Cardona picked up a friend, then they went to the accused killer's home. 

Beige trailer with a bedroom window boarded up.

Colorado teenager Sirio-Cardona is acccused of fatally shooting his ex-girlfriend, Lily Silva-Lopez, at her family's home, pictured, after crawling through her bedroom window. (FOX31)

Officers arrived later that afternoon, and his grandmother asked why they were there. According to his arrest affidavit, Sirio-Cardona replied that "he did what he had to do, and he shot someone."

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Sirio-Cardona, who is being tried as an adult, is charged with first-degree murder, second-degree murder, first-degree burglary, aggravated robbery and possession of a handgun by a juvenile. 

He's being held on a $2,000,000 bond and is due back in court Aug. 3.