The Ohio woman, her young son and a family friend, whose bodies were found wrapped in garbage bags and stuffed in a hollow tree, were all repeatedly stabbed in the back and dismembered after they died, according to a preliminary coroner's report released today.
It did not appear -- "pending further tests" -- that any of the three were sexually assaulted, the autopsy report said.
"The most challenging and heartbreaking thing I have had to do as coroner is discuss these findings with the families of the deceased victims," Knox County corner J.F. Ogle said today. "The truth is often unspeakable."
The bodies of Tina Herrmann, 31, Stephanie Sprang, 41, and Kody Maynard, 11, were found Thursday afternoon in large plastic garbage bags, stuffed in a hollow tree.
The three, along with Herrmann's 13-year-old daughter Sarah Maynard, disappeared Nov. 10. According to the autopsy, all three were killed the same day.
Sarah was found Sunday, bound and gagged but alive, when a SWAT team stormed the home of Matthew Hoffman, who was arrested and charged with kidnapping.
"The story of Sarah Maynard's rescue will forever be remembered as an example of extraordinary detective work and bravery," Ogle said today.
Though the bodies of Herrmann, Sprang and Kody Maynard were discovered in the Kokosing Lake State Wildlife Area in Knox County, it was still not clear where the three were killed, according to the autopsy report.
The cause of death for all three was loss of blood as a result of the wounds in their backs, but all three also suffered additional wounds, according to the report.
"They were then placed inside large plastic garbage bags and later lowered into the hollow of a large tree," the report said.
The dismembered bodies were found with the remains of the family's miniature pinscher, Tanner, said a family friend Joe Pejsa, according to The Associated Press.
The final coroner's report will take six to eight weeks, Ogle said.
Knox County Sheriff David Barber said Thursday that Hoffman's lawyers told them where to find the victims.
"The discovery of these bodies was the result of information provided by Matthew Hoffman," Barber said. "We were optimistic a few days ago that there was a remote chance these persons were still alive. This is a homicide investigation now."
Authorities said they had been contacted by Hoffman's lawyer but would not characterize the information as a confession. The county prosecutor would not say whether officials had cut a deal to encourage Hoffman to talk.
Barber said there were no other suspects involved, and would not speculate on a motive.
The bodies were found near Apple Valley, Ohio, miles away from Hoffman's home where Sarah was found on Sunday by a SWAT team. The girl was bound and gagged in Hoffman's basement in rural Mount Vernon, Ohio.
Barber said he believed the victims were killed in their blood-splattered house in Howard, Ohio, about 10 miles from where Hoffman lived. The sheriff said Sarah was also at home at the time, but wouldn't say whether she witnessed the killings.
Hoffman is a 31-year-old drifter who had recently been released from a Colorado prison after serving a term for arson and burglary.
Hoffman has been in police custody since Sunday, but has not previously cooperated with investigators.
Barber said police had to cut into the tree to remove the three bodies. He said the victims were all wearing the same clothes they had last been seen in on Nov. 10.
Barber suggested that Hoffman had hollowed out the tree himself saying, "Hoffman has worked as tree trimmer."
Knox County prosecutor John Thatcher said Hoffman would likely be brought up on additional charges.
"I can't speculate on what those charges might be without knowing what the evidence is," said Thatcher.
Hoffman is scheduled to appear in court again Tuesday.
Both Barber and Thatcher appeared emotional at times, calling the case one of the worst they had ever encountered.
"The tragedy today is just devastating," said Thatcher. "The results aren't what we wanted them to be."
Police immediately focused the search for Sarah's family members near Hoffman's home, homing in on a park a short walk from the house where he kept the girl confined.
Police said that after his arrest Hoffman was placed on suicide watch and had not been cooperating with their investigation. He appeared in court Tuesday wearing an anti-suicide smock, and his bail was set at $1 million.
Police said Sarah was in good health, staying with her father and cooperating with the investigation.
All four people were last seen Nov. 10 at the family home in Howard, Ohio, about 10 miles from Hoffman's house in Mount Vernon. Police were initially called to the family's home when Herrmann did not show up for work at a local Dairy Queen. When police searched the home, they found it splattered with blood.
Early on in the investigation, Police temporarily locked down nearby Kenyon College when Hermann's pickup truck was found parked on the campus one day after cops had observed it in the family's driveway.
The only known connection between Hoffman and Maynard and her family is that Hoffman's parents live within walking distance of Maynard's mother's home.
Neighbors described Hoffman's behavior as "bizarre," saying they would see him climbing trees, spying on them from the boughs, building fires on his front lawn and killing small animals.
"He was killing the squirrels because he doesn't grocery shop," neighbor Kara Fowler told ABC News. "He would actually kill the squirrels and eat them."
ABC News' Russell Goldman contributed to this report.