Okla. Dad Kills 2 Daughters in Murder-Suicide After Threats to Their Mom, Who Heard Gunshot on Phone

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Days after dealing with a triple murder-suicide involving two young girls, police in Sand Springs, Oklahoma, found themselves at the scene of another murder-suicide, in which a father killed his two teenage daughters.

Local reports, citing police, state Clarissa Kaser, 19, and her 14-year-old sister, Crystal "Grey" Kaser, were fatally shot Tuesday.

Police believe their dad, David Kaser, 56, killed both girls before turning the gun on himself, according to the Tulsa World.

Investigators have determined a motive for the violence, but will not be sharing it with the public, reports KTUL.

Clarissa was a recent graduate of Charles Page High School in Sand Springs, while Crystal was a ninth grader at nearby Clyde Boyd Middle School.

According to KOTV, the girls' mother told police that David Kaser called her while she was at work, threatening to kill their children.

Police said that she reported hearing a gunshot during that terrifying call.

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The Sand Springs School District addressed Tuesday's tragedy in a social media post the following morning.

"Our hearts are heavy for the recent tragedies of two Sand Springs families," the statement reads. "Our condolences go out to each of these families."

It adds: "For most, the local public school is the heart of the community, and Sand Springs is a prime example of this. Sandites are a source of strength and resolve, and words cannot express how thankful we are for this community."

A GoFundMe campaign, launched by the victims' brother, Kenan, will help defray the costs of their girls' funerals. Kenan wrote that David had "multiple debts" that the mom is now legally responsible for.

"My sisters loved life, very much," reads the page. "They both had wonderful plans for the future, things looked bright. My father stole their futures."