An Idaho coroner has revealed the cause of death for four University of Idaho students who were killed earlier this week.
Ethan Chapin, 20, Madison Mogen, 21, Xana Kernodle, 20, and Kaylee Goncalves, 21,were found deadin an off-campus apartment on Sunday.
Their deaths were officially ruled homicides.
Mabbutt did not immediately respond to PEOPLE’s request for comment.
She told NBC News that authoritiessuspect a large knife was used.
“It would have had to have been … not a pocket knife,” she said. “It would have been a bigger knife.”
Ethan Chapin, Madison Mogen, Kaylee Goncalves and Xana Kernodle.

Mabbutt, who was worked as a coroner for 16 years, also told the outlet that their wounds “were pretty extensive” and the crime scene was unlike anything she’d experienced before.
“We have had multiple murders in the past, but nothing like this with four college students,” she said.
Toxicology results for the victims are still pending.
Ethan Chapin, Madison Mogen, Xana Kernodle, and Kaylee Goncalves.Instagram

Latah County Prosecutor Bill Thompson also saidwhile onTODAYthat it’s possible there are multiple suspects.
“At this point, the investigators are looking at all possibilities. They don’t have a specific suspect,” he said. “We’re really hoping for any information from the public to help recreate everyone’s activities.”
RELATED VIDEO: 4 Idaho Students Were Killed in Apparent Knife Attack — Was It ‘Crime of Passion’ or ‘Burglary Gone Wrong?’
In apress releaseon Tuesday, authorities confirmed thatno weapons have been found, but “based on preliminary information, investigators believe that an edged weapon such as a knife was used” in the killings.
Moscow Mayor Art Bettge toldFox Newsthat the crime occurred around 3 or 4 in the morning on Sunday, but was reported to police around noon.
He confirmed that the reason behind the killings was still being investigated, but said it could have been a “burglary gone wrong” or a “crime of passion,” Fox News reports.
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“It’s one of any of a plenitude of possibilities, including burglary gone wrong, robbery gone wrong … Any of those is a possibility and not one to the exclusion of others,” Bettge said, Fox News reports.
“It is impossible to understand the senselessness of events like this, and we all are seeking answers that are not yet available,” Bettge said in astatement.
During a Wednesday press conference, Moscow Police Chief James Fry said, “We do not have a suspect at this time, and that individual is still out there. We cannot say there is no threat to the community.”
He stressed that the community should “remain vigilant.”
source: people.com