BOISE, Idaho >> Autopsies have been completed on four University of Idaho students who were found stabbed to death inside a rental house near campus, and the results have been forwarded to law enforcement, the Spokane County Medical Examiner said Thursday.

The bodies were then released to the victims’ families, and the results of the examinations were likely to be released later in the day.

The killings have shaken Moscow, an Idaho Panhandle college town of 25,000 residents that last saw a homicide five years ago, according to Latah County Coroner Cathy Mabbutt.

“It’s pretty tough,” Mabbutt said.

Here is a look at what is known about the killings, and what remains a mystery:

IS THERE A SUSPECT?

Officers have not identified a suspect or found a blade that was used to stab the students, Moscow Police Chief James Fry said Wednesday. But the Idaho Statesman reported this week that police are searching for a military-style knife in connection with the killings. Scott Jutte, general manager of Moscow Building Supply, told the newspaper that officers have visited the store more than once to ask whether it sold anyone Ka-Bar-brand knives. Ka-Bar, of Olean, New York, manufactures military-grade blades that were originally designed for use by American troops in World War II, the Statesman said.

WHO ARE THE VICTIMS?

All four were University of Idaho students and members of fraternities and sororities: seniors Madison Mogen, 21, of Coeur d’Alene, Idaho, and Kaylee Goncalves, 21, of Rathdrum, Idaho; junior Xana Kernodle, 20, of Post Falls, Idaho; and freshman Ethan Chapin, 20, of Mount Vernon, Washington. The women were roommates. The bodies were found around noon Sunday.

DID THE KILLER OR KILLERS KNOW THE VICTIMS?

It’s unclear. Police have said evidence found at the scene leads them to believe that the students were targeted, though they haven’t given details. While a targeted attack is often an indication that the killer and victim knew each other on some level, police have also said they have no idea who committed these crimes, so it could have been a stranger. Investigators do say nothing appears to have been stolen from the victims or the home.

DID THE STUDENTS RAISE SECURITY CONCERNS BEFOREHAND?

Police have not said whether any of them reported unusual activity or otherwise expressed safety concerns before the attack. The University of Idaho did not respond to questions about whether the school had been alerted to any concerns or complaints from the students.

IS THERE ANY THREAT TO THE COMMUNITY?

After initially saying there was no ongoing danger, police walked that back on Wednesday. “We cannot say that there is no threat to the community,” Fry said. “We still believe it’s a targeted attack. But the reality is there still is a person out there who committed four very horrible, horrible crimes.”

WHO ELSE WAS IN THE HOME?

Two other people were found in the sprawling house, unharmed. Fry declined to say whether they were able to provide an account of the killings, or to specify who called 911. When a reporter referred to the surviving roommates as witnesses, Fry clarified: “I don’t think I ever said they were witnesses. I said they were there.” There was no sign of forced entry at the home, according to the chief, and a door was found open by the first police officers to arrive.

WHEN WERE THE STUDENTS LAST SEEN ALIVE?

Chapin and Kernodle were at a party on campus Saturday night, and Mogen and Goncalves were at a downtown bar and arrived home sometime after 1:45 a.m. Sunday, Fry said. Mogen and Goncalves were seen in a Twitch livestream getting food from a local truck.

WHAT’S HAPPENING ON CAMPUS?

University of Idaho president Scott Green said the school will remain open the rest of the week because some students have found comfort there among faculty and classmates. But the school is also giving excused absences to anyone who feels more comfortable leaving early ahead of next week’s Thanksgiving holiday.