Investigators have provided few answers about the stabbing deaths of four University of Idaho students in mid-November, leading to increased unease in the small community of Moscow, Idaho.

The victims included three out of the five roommates of a multi-level home —Madison Mogen, 21; Kaylee Goncalves, 21; and Xana Kernodle, 20 — as well as Ethan Chapin, 20, a boyfriend of one of the roommates. Investigators have found a sixth resident who was signed onto the lease but who had moved out prior to the beginning of the school year and was not present at the time of the slayings.

Victims' families and the town public have grown frustrated with the three-week-long investigation which has been riddled with contradictions by investigative officials.

Local authorities, who have not investigated a homicide case since 2015, had initially said the stabbings were an "isolated targeted attack" and that there was "no imminent threat" to the public.

On Nov. 16, Moscow Police Chief James Fry made a statement that contradicted the department's initial directions. "We cannot say there's no threat to the community and as we have stated, please stay vigilant, report any suspicious activity and be aware of your surroundings at all times," Fry said.

Another source of confusion for local residents is a comment from Latah County prosecutor Bill Thompson, who said that "investigators believe that whoever is responsible was specifically looking at this particular residence," during a NewsNation interview on Tuesday.

On Wednesday, Moscow police said Thompson's statement was not true and was due to a miscommunication between the departments.

"Detectives do not currently know if the residence or any occupants were specifically targeted but continue to investigate. At this time, there is no change or new information in this case, and references otherwise would be inaccurate," authorities said.

Local Moscow City police are working alongside the Idaho State Police, the Latah County Sheriff's Office and the FBI. Authorities say they have accumulated over 100 pieces of evidence, 4,000 photos, and 1,000 tips. They have also conducted 150 interviews.

The involvement of federal law enforcement is expected to improve the efficiency of the investigation. The FBI has assigned 40 officers to the case, planning to utilize cross-referenced DNA data as well as the bureau's violent criminal apprehension program, which analyzes similar crimes and suspects across the country.

One of the victim's fathers, Steve Goncalves, expressed frustration with the investigation.

"I don't like it one bit," Goncalves told Fox News on Sunday.

"I know these statements take hours and multiple individuals to review. It's not like this was something said on the side of the street within the first five hours of the case.

"These guys are professionals. They sat in a room and this is what they came out with? They keep coming out with statements that create more questions than they answer. And then that creates a pressure."

He says that his family has halted their funeral plans out of fear that the killer may be present.

"My wife's biggest fear, part of the reason we didn't have a funeral, is because she couldn't be guaranteed that that monster was going to not be there," Goncalves said. "I haven't earned the ability to grieve the way that I want. I want to be able to have justice first."

Crime experts say that the reason for confusing statements may be the police's need to keep suspect and crime knowledge confidential while providing the media and public with adequate information.

"Sometimes you have to keep a tight lip about what you know, and as an investigator, you definitely don't want to show your cards," retired detective Alison Sullivan told USA Today.

Although police statements continue to fuel the anxiety for the town of 26,000, some evidence is continuing to mount.

Forensic scientist Carole Lieberman said she believes the suspect is a man due to the brutality of the killings involving four victims. "For a person to make that many stab wounds to four people in a relatively short amount of time, they have to be physically strong," Lieberman said.

Police believe the murder weapon to be a fixed-blade knife and have contacted local retailers to see if they have sold similar knives recently. They are relying on DNA evidence to provide information on a possible suspect.

"From my investigative experience, the ability for a suspect to enter a dwelling and leave without leaving substantial trace evidence is very unlikely," Sullivan said. "In this case, you're literally quadrupling the chances that the suspect left some type of trace evidence."

The two surviving roommates — Dylan Mortensen and Bethany Funke — wrote letters that were read by a pastor this weekend at a memorial service for the victims. Mortensen and Funke were on the ground floor of the home during the killings on the second and third floors. Police say they likely slept through the attack and have been ruled out as suspects.

"They all lit up any room they walked into and were gifts to this world. I wish every day that I could give them all one last hug and say how much I loved them," one of the letters wrote.