MORRISVILLE, Pa. — Five family members, including a New Jersey mom and her two daughters, were found dead in an apartment in Pennsylvania. Officials say they were killed by two of their relatives, including a mother who took the lives of two of her children.

Jamilla Campbell, 42, of Trenton, her 9-year-old twin daughters Imani and Erika Allen, and her niece and nephew, Naa’Irah Smith, 25, and Damon Decree Jr., 13, both of Morrisville, were killed sometime before Monday afternoon, authorities said.

Campbell's sister and niece — Shana S. Decree, 45, and Dominique Decree, 19 — were charged with homicide and conspiracy.

The bodies were found Monday afternoon in a first-floor bedroom of the Robert Morris Apartments on West Bridge Street, according to Bucks County District Attorney Matthew Weintraub, who did not disclose how the victims were killed or why.

Shana and Dominique were found inside the apartment when they were taken into custody, according to Weintraub. The two women were hospitalized.

"This is a terrible tragedy. I just spoke with the family of the five of the deceased and we're all heartbroken," Weintraub said at a news conference on Monday night.

Weintraub said that investigators are also looking for Jamilla Campbell's 17-year-old son Joshua, although he is not considered a suspect.

A friend of the victims told NBC Philadelphia that police were conducting a welfare check at the apartment after trash had piled up outside.

Contact reporter Dan Alexander at Dan.Alexander@townsquaremedia.com or via Twitter @DanAlexanderNJ.

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