According to a new release sent from the Bucks County district attorney's office on Friday, the medical examiner determined that four of the victims, 9-year-old twin sisters Imani and Erika Allen, 13-year-old Damon Decree Jr., and 25-year-old Naa'Irah Smith died by asphyxiation.
42-year-old Jamilla Campbell, the mother of the twin girls, died from strangulation, the medical examiner ruled.
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The Bucks County district attorney's office said the manner of death for each victim was ruled homicide.
No further details were released.
Two women, 46-year-old Shana Decree and her 19-year-old daughter, Dominique, each face five counts of criminal homicide and one count of criminal conspiracy.
The bodies of the five victims were discovered inside a bedroom at the Robert Morris Apartments on West Bridge Street back on February 25.
In an interview with Action News shortly after the killings, Damon Decree Sr. suggested the suspects could have been involved in a cult.
However, police said at the time there was no evidence of cult activity in this case.
Action News is told Bucks County Children and Youth Social Services Agency performed a welfare check at the Robert Morris Apartments on the 200 block of West Bridge Street the previous Saturday, but when no one answered, a worker left a card.
According to an affidavit of probable cause, representatives returned to apartment 5S for an unannounced visit around 4 p.m. Monday. After there was no answer, the representative contacted a maintenance worker at the complex.
When the maintenance worker gained access to the apartment, he found two women, identified as Shana and Dominique Decree, in bed. The worker reported that the two seemed disoriented and the apartment was in disarray. Morrisville police were called to the scene and both were taken to the hospital.
Arriving officers saw furniture upended in the apartment, along with broken glass and clutter. The Children and Youth representative told police the apartment was not in disarray during their last visit in early February.
Police initially saw four bodies in a small bedroom. The fifth was later discovered underneath another body.
Authorities say Dominique had visible injuries to her neck and, at first, denied knowing what happened. She claimed that an unknown male hurt her and she kept repeating she wanted to die.
Shana also first denied knowing what happened, according to police, claiming her sister's boyfriend and two unknown males came into the apartment and killed everyone except her and her daughter.
Dominique separately then echoed claims about her aunt's boyfriend and two unknown males.
The affidavit indicates that later, Shana told police everyone in the apartment, including the 9-year-old twins and 13-year-old, wanted to die and was talking about suicide.