Brother, 18, and sister, 20, stabbed to death at home

WARNING - GRAPHIC DETAILS: Siblings Zachery Hulbert, 18, and Ryan Hulbert, 20, were found stabbed to death in their home on Monday morning (local time) after the latter split with her boyfriend.

Police allege Garrett Leyva, 20, Ryan's former partner of two years, admitted to killing the bother and sister at an address is Hanford California while on the phone to emergency services.

He was also suffering stab wounds, investigators said.

Siblings Ryan Hulbert (left) and Zachery Hulbert (right)
Ryan Hulbert (left) and her brother Zachery Hulbert (left) were stabbed to death on Monday. The suspect is believed to be Ryan's ex-boyfriend. Source: GoFundMe

"He was upset over that break-up and that's what led to the altercation," Hanford Police Chief Parker Sever told ABC News.

He said crimes like these were hard on family members, as well as first responders who attend them.

“I think it’s pretty clear what happened. However, these are never easy cases, they are hard for family members they are hard for our law enforcement agencies who respond to it and they are terrible crimes when they occur,” Chief Sever told local media outlet Your Central Valley.

Neighbours from area in the San Joaquin Valley said watching police swarm the street and wheel out the suspect on a stretcher didn't feel real.

Family and friends gathered near the home to console each other as police investigated the crime scene.

“Honestly it felt like a movie, man. It felt fake but once you kind of get closer reality hits you,” neighbour Edgar Amezola told Your Central Valley.

“I’m a father of four so I wouldn’t want anybody to feel that feeling but unfortunately, today was a sad day,”

double homicide suspect, Garrett Leyva
The suspect, Garrett Leyva, was filmed being placed into an ambulance with stab wounds. Source: yourcentralvalley.com

Chief Sever told ABC News he spoke to the mum of the victims, who was at work when the alleged murder happened.

"I made sure I told the mum that this is not her fault," he said.

"It's not the fault of her daughter. There's only one person that's responsible for this crime and that's the person that committed it."

A GoFundMe page has been set up to help support the Hulbert family.

Investigations continue.

If you or someone you know is a victim of domestic violence, find help by visiting Lifeline or calling 1800 RESPECT.

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