State police previously announced they were investigating the deaths of Tracey Adams and Brandi Hauck, who they said were found at 844 Malta Road around 5 p.m.
Investigators now say Adams was involved in a "verbal and physical" domestic dispute at a house on Adams Road earlier in the evening. The fight caused an adult woman and a daughter of Adams' to flee the home and go to Hauck's house on Malta Road, troopers said in a release.
Adams' juvenile son was also at the Malta Road home when the 47-year-old dad approached the front door brandishing a pistol, according to police.
When Hauck demanded that he leave the property, troopers said Adams shot her through the door. She died from her wounds at the scene, police said.
Adams then "declared his intention to kill everyone" in the house, the release says.
As he forced his way inside, troopers said Adams' juvenile son shielded the others and shot his father "as he advanced towards them." Adams' wounds were fatal and he succumbed at the scene, police added.
Northumberland County District Attorney Michael O'Donnell has declined to press charges, "due to the nature of shooting being self-defense and preservation of life," the release concludes.
Loved ones are accepting donations on GoFundMe for Hauck's memorial fund, an effort that has raised nearly $10,000 in less than 12 hours as of Wednesday evening, Jan. 10.
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