The deaths of four University of Idaho students found stabbed over the weekend were officially ruled homicides, authorities said. 

Latah County Coroner Cathy Mabbutt said the manner of death was a stabbing for all four individuals. The cause of death was murder, according to Mabbutt.

The victims are Ethan Chapin, 20; Madison Mogen, 21; Xana Kernodle, 20; and Kaylee Goncalves, 21, who police say were attacked with an "edged weapon," likely a knife.

UNIVERSITY OF IDAHO MURDERS TIMELINE: WHAT WE KNOW ABOUT THE SLAUGHTER OF FOUR STUDENTS

A split photo of the deceased students.

From left, University of Idaho students Ethan Chapin, 20; Xana Kernodle, 20; Madison Mogen, 21; and Kaylee Goncalves, 21. (Jazzmin Kernodle via AP/Instagram/ @kayleegoncalves)

Mabbutt, who wrapped up the autopsies Wednesday, previously said the killings were not a murder-suicide. The toxicology reports are still outstanding. She said the same knife was likely used to kill all four victims. 

UNIVERSITY OF IDAHO MURDERS: TWO ROOMMATES WERE AT HOME WHEN FOUR STUDENTS WERE KILLED

Police have not recovered a weapon or publicly identified a suspect in the quadruple homicide, which has shaken the small town of 25,000 people. 

Ka-Bar knife inset in front of house where students were murdered.

Police suspect a Ka-Bar knife may have been used in slayings of four University Idaho students, inset. Caution tape surrounds the house near campus where the students were slaughtered. (Ka-Bar / Derek Shook for Fox News Digital)

Scott Jutte, a manager at Moscow Building Supply, told the Idaho Statesman that police had come by more than once asking if the store had sold any Ka-Bar brand knives, which they do not carry. The combat knife looks like the one used by Rambo, Jutte added. 

Latah County Prosecutor Bill Thompson told NBC News that it's possible there's more than one suspect.

UNIVERSITY OF IDAHO MURDERS: BLOOD SEEN OOZING FROM HOUSE AMID REPORTS OF PREVIOUS THREAT

"It certainly is possible. That's the purpose of the investigation, that's why we're really hoping for any information from the public that can help the investigators recreate everyone's activities from Saturday night into early Sunday morning and hopefully give them the leads, the information, to identify who did this," Thompson said.

UNIVERSITY OF IDAHO MURDERS: THREAT STILL POSSIBLE WITHOUT ANY SUSPECTS IN CUSTODY, POLICE SAY

In a press conference Wednesday, Moscow Police Chief James Fry urged locals to "stay vigilant" as the "individual is still out there."

University of Idaho students found dead

The four victims in the University of Idaho slayings (Instagram: @kayleegoncalves)

Police came upon a gruesome scene at noon Sunday after responding to a 911 call of an "unconscious individual" at the King Road home, where the victims and two female roommates lived.

CLICK HERE TO GET THE FOX NEWS APP

The roommates were home when the students were killed between 3 a.m. and 4 a.m., Fry said.

The FBI and the Idaho State Police are assisting in the investigation.