- Police: Escort killed Neal Falls after he attempted to rape her
- Handcuffs, bleach, multiple weapons discovered in Falls' trunk
- Police in Illinois, Nevada looking for links between Falls, unsolved deaths
(CNN)"He pulled a gun on me! He was going to kill me!"
Those are the chilling words caught in the background of a 911 call placed earlier this month after a woman faced off with an attacker who tried to rape her, pointing a 9 mm gun to her chest.
The victim, who is being called "Heather" by investigators, fought back so hard, police in Charleston, West Virginia said, that her attacker -- who police now believe may be linked to other crimes -- lost control of his gun.
Heather grabbed the weapon and blindly fired it, killing 45-year-old Neal Falls in self-defense, police said.
Heather, who met Falls after connecting via the escort section of backpage.com, was not charged in the incident.
Because the offender died during the crime, "our case is closed," according to Lt. Steve Cooper, chief of detectives of the Charleston, West Virginia, Police Department.
But while the West Virginia part of the story might be over, what police discovered in the trunk of Falls' car has investigators in other states wondering if he could be linked to other unsolved cases involving escorts.
Cooper said Falls had what police are calling a "kill kit," which included four sets of handcuffs, an ax, a machete, bulletproof vests, knives, a box cutter, a large container of bleach, and a large number of trash bags.
Police say it's unlikely this was the 45-year-old Falls' first violent crime.
The FBI said Tuesday that while there is no information that connects him with any unsolved killings, it will explore the possibility.
'I knew he was there to kill me'
The last person to see Falls alive said she knew her attacker had experience committing violence.
"I knew he was there to kill me," Heather told CNN affiliate WCSH, "I could tell he had already done something because he said he was going to prison for a long time."
Police said Falls also carried a list of about 10 women -- all escorts in West Virginia -- along with their ages and phone numbers. Those women are all alive and have not had any previous contact with Falls, Cooper said.
The nature of the crimes and where the crimes occurred have also given officials pause.
In 2005, Falls lived in Las Vegas, the same year four women who were working as escorts in the area disappeared. Their dismembered bodies were later discovered in Illinois.
One of those women, Lindsay Marie Harris, was 21 when she disappeared from Henderson, Nevada, in May 2005. Her legs were found in Springfield, Illinois, three weeks later.
Representatives from the Henderson and Illinois State Police departments both confirm they have been in contact with officials in Charleston.
"Our role is simply to share DNA, other crime-scene information, and witness and victim information with any other agency that wants to compare their cases with this one," Cooper said.
The Las Vegas Police Department has not returned CNN's calls for comment.
Falls' car had an Oregon license plate, and he is believed to have lived in that state for a time, though police couldn't say for sure when he was last a resident.
Landlord: He was a 'little creepy'
CNN spoke to a woman in Eugene, Oregon, who said she is Falls' sister. She said she wants nothing to do with her brother and that the family will have no further comment.
Falls' former landlord told CNN affiliate KVAL that Falls lived at her house in 2010. The woman, who asked to be identified only as Pauline, said she evicted Falls after one year because his strange behavior made her uncomfortable.
"The first thing that he did that was a little odd was that he immediately changed the deadbolt to his own room so that only he had a key," Pauline told KVAL. "He said he had guns and weapons and that he was a security guard."
Springfield, Oregon, Police Sgt. Rich Charboneau said his department had some contact with Falls during the last few years for minor offenses like traffic tickets and a dog at large.
Falls also filed a complaint against someone else for trespassing on his property.
"Little creepy, very tightly lipped and not a chummy guy, definitely not a chummy guy," Pauline said. "Somebody who doesn't like to be exposed."
No connection to missing Ohio women, authorities say
Though there are no open murder investigations in Springfield, police have assigned a homicide detective to work as a liaison with officials in West Virginia, Charboneau said.
With just 120 miles separating Charleston, West Virginia, and Chillicothe, Ohio, officials had considered a possible connection between Falls and six women who have gone missing or have turned up dead in a little more than a year.
But that connection has been ruled out.
"There is nothing whatsoever that can tie him to the missing women in Chillicothe," said Lt. Michael E. Preston, spokesman for Ross County Sheriff's Office.