Authorities have said Stone, 35, a former Marine, went on a 90-minute shooting and slashing rampage before daybreak Dec. 15 at three homes within a few miles of one another in the Montgomery County towns of Lansdale, Lower Salford Township and Souderton.
Stone's ex-wife, Nicole Stone, was killed, as were her mother, grandmother, sister, brother-in-law and teenage niece. The deaths were ruled homicides. A teenage nephew was the only survivor of the attacks, authorities said.
Officials said Stone and his ex-wife were embroiled in a custody battle over their two daughters. The couple divorced in 2009.
According to an autopsy conducted by the county coroner's office, Stone committed suicide by ingesting trazodone, risperidone and mCPP.
Stone's body was found the day after the attacks in a nearby wooded area. Next to his body — which had a stab wound on an upper thigh, scratches on the face and neck and some superficial cuts — were medicine bottles with crushed powder inside and an open energy drink with powder in the lip, according to details released Tuesday by the Montgomery County district attorney. Last week, officials said Stone appeared to have killed himself with a knife.
Also found near his body were two bloodied knives, a large machete and a double-bladed axe, the district attorney's office said.
Officials say the rampage began between 3:30 and 4 a.m. Dec. 15, when Stone entered the Flick home and attacked his ex-wife's sister and her husband and two children. Trisha Flick, 36, died of gunshot wounds to the arm and head, the coroner determined; her husband, Aaron Flick, 39, and daughter Nina Flick, 14, were found with "chop wounds" on their heads and necks.
Anthony Flick, 17, the sole survivor, suffered "chopping" wounds to his head and hands and was released from the hospital Monday, officials said.
Officials say Stone continued his rampage in Lansdale about 4:25 a.m., fatally shooting his ex-wife's mother and grandmother: Joanne Gilbert, 57, and Patricia Hill, 75.
Stone then went to his ex-wife's home in Lower Salford, shooting her in the hand and head at about 4:55 a.m., officials said. At her home, police recovered a .40-caliber handgun that officials said Stone bought in 2011 and used in the Dec. 15 shootings.
Around 5 a.m., Stone "delivered" his two daughters to a neighbor in Pennsburg, Montgomery County Dist. Atty. Risa Vetri Ferman told reporters last week. The girls, thought to be about 5 and 7 years old, were in protective custody, Ferman said at the time, adding: "They are safe, they are secure."
Stone was not supposed to have any firearms. In 2013, he was admitted to a veterans' treatment court program after being charged with driving under the influence. He was supposed to take part in the program for nearly two years, during which time he was banned from owning, possessing or using guns and barred from hunting, according to authorities.
Between Nov. 15, 2013, and Dec. 5, 2014, police said, Stone appeared in court 22 times and received 17 home visits from probation officers. None of those officers found weapons on Stone or in his home, authorities said.
The day after the killings, police searched his home and found a small-caliber rifle that was "in pieces and was inoperable."
When they searched his home again Tuesday, they found hidden in the attic a .22-caliber rifle engraved with Stone's father's name, officials said.
According to authorities, Nicole Stone secured a temporary restraining order against her ex-husband in September 2010, but it expired 10 days later, and her application for a permanent order was denied.