A 20-year-old word search puzzle created by an infamous US serial killer has given investigators a clue to another unsolved case — a missing girl's name.
Warning: This story contains content which may be distressing for some readers.
The puzzle was first sent to a news station by convicted killer Dennis Rader in 2004, but only a handful of words relevant to the crime were found at the time.
That was until last month when detectives received a package from an anonymous woman.
Rader, also known as BTK — "Bind, Torture, Kill" — murdered at least 10 people in Kansas between 1974 and 1991.
Similarities between missing person case and serial killings
Cynthia Dawn Kinney was just 16 years old when she vanished from a laundromat in Pawhuska, Oklahoma, on June 23, 1976.
The teen — called Cindy by most who knew her — was filling in for a friend who worked at the Osage Laundry.
"She actually specified that she needed to be out of the laundromat by the time she had to be at cheerleading that day," Osage County Undersheriff Gary Upton told news station KSN.
There was no sign of a struggle. Some loose change and a half-eaten doughnut were left inside the laundromat.
For decades her family has searched for answers, with police receiving multiple tips and potential suspects all leading nowhere.
"I just can't understand. It's just so heavy for me," her father, Don Kinney, told KSN in 2023.
"We went 50 years thinking every time somebody had something, well, I hope this sheriff does."
Since last year, police have been working on a different theory — that Cindy Kinney may have fallen victim to BTK.
Osage County Sheriff Eddie Virden said the idea first occurred to him in the midst of a separate homicide investigation.
"[It was a] pretty complicated case … I woke up 1:30 something in the morning, tossed around, couldn't get back to sleep," he said.
"I thought, 'I'm just going to get up,' so I go and make a pot of coffee, flip on the TV [and] there's a documentary on about the BTK killer.
"I'm sitting there, drinking coffee, waiting for daylight. As I'm watching it, things start kind of popping out that are familiar."
'Good luck hunting' after multiple murders
Rader hid in plain sight in the Kansas suburbs for years.
The city ordinance enforcement officer and scout troop leader had a wife and two children when he committed his first known murder in 1974.
He had grown up in Wichita, and later admitted to harbouring sadistic fantasies and torturing small animals from an early age.
He also craved attention for his crimes.
Letters, poems and puzzles were sent to media outlets and stashed in library books between each killing.
A month after killing four members of the Otero family, he sent a letter to The Wichita Eagle newspaper.
"Those three dudes you have in custody are just talking to get publicity for the Otero murders," he wrote.
"They know nothing at all. I did it by myself and with no one's help … I can't stop it, so the monster goes on … Good luck hunting."
At the end of the letter, he suggested his own moniker by signing off: "Bind them, torture them, kill them. BTK."
1974: The Otero family
Joseph and Julie Otero, along with two of their five children — Joey, 9, and Josie, 11 — were killed on January 15, 1974.
Mr Otero, 38, was a former US Air Force sergeant and technician, and the family had moved back to the US from their native Puerto Rico just weeks earlier.
That morning, a 28-year-old Rader cut the phone lines and entered the house through the back door when Joey opened it to let the dog out into the yard.
He had been stalking the family for weeks and making meticulous notes.
Their bodies were found by the older children when they arrived home from school that afternoon.
Charlie Otero, just 15 years old at the time of the murders, said in a later interview his heart "just got ripped out of my chest".
"The day Dennis Rader was caught I was working landscaping … I got the phone call from my sister, I said, 'Yeah, right,'" he said.
"I put the phone down and I remember bushes flying 10 feet high over my head. I was ripping them out of the ground."
1974: Kathryn Bright
Kathryn Bright, 21, was an assembly line worker at the same company Julie Otero had previously worked at.
Her cousin, Marcia Brown, told The Wichita Eagle Ms Bright's name "fit her well".
"She was beautiful, funny, popular. And bright, too," Ms Brown said in 2005.
"When I think of Kathy, I think of laughter. She was just a fun person to be around … If she wasn't making me laugh, she was laughing herself. She was such a free spirit."
She returned home with her brother, 19-year-old Kevin Bright, at about 2pm on April 4, 1974, to find a man with a gun waiting inside the house for them.
The siblings were tied up in separate rooms. Kevin pretended to be dead and was shot three times in the head, but managed to free himself and flee.
Decades after the attack, he would be left with lead fragments in his skull.
"If [Rader] had something uncontrollable inside him, why didn't he seek help instead of ruining everybody's life?" he said in 2005.
1977: Shirley Vian Relford
Shirley Vian Relford, 26, was dealing with a case of the flu on March 17, 1977, when she called a nearby supermarket and told staff she was sending one of her three children to get food.
Steven Relford walked to the shop a block away from the family home, bought soup, and went home. It was the wrong kind. His mother sent him back.
Returning a second time, a man with a briefcase followed him.
For years after, the moment would haunt him: "I let the BTK into my house."
The man went to a nearby house but knocked on the door a few minutes later, which is when the five-year-old boy opened the door.
Rader locked the children in the bathroom with toys and blankets while he killed their mother.
"[I want to ask] what possessed him to kill my mother and these other innocent folks out here," Steven Relford told CNN following Rader's arrest. "He had no right."
1977: Nancy Jo Fox
Nancy Fox was living alone and working multiple jobs when she was murdered on December 8, 1977.
Her coworker Cindy Duckett told The Wichita Eagle that Nancy "smiled a lot".
"She joked a lot … she did have worries," she said.
"She had bills to pay, and she was responsible for herself. She was more mature than the rest of the girls."
The day after killing Ms Duckett, Rader called police from a public phone booth to report the crime.
Her family did not recognise the voice when a recording of the call was played for them.
Her sister, Beverly, told a 2019 documentary: "She was very outgoing, very friendly. She was one to speak her mind. She didn't keep quiet."
1985: Marine Hedge
Marine Hedge was a 53-year-old grandmother living in Park City just a few houses down from Rader.
Her husband had died a year before, and she spent her days going to bingo, working in the yard and attending church.
"She talked like Dolly Parton, she was amazingly sweet," her daughter-in-law Phyllis Hedge told The Wichita Eagle in 2005.
"I just remember Thanksgiving when we came. Everything you can imagine was just ready … everything she [cooked] was from the heart.
"She was adored by her son. [She was] the most wonderful woman on Earth."
She was killed on April 27, 1985. Rader took photographs of her body at his church before disposing of it.
1986: Vicki Wegerle
Vicki Lynn Wegerle, 28, had a two-year-old son and a nine-year-old daughter, who she looked after during the day while her husband worked.
She volunteered as a babysitter for neighbours and at nearby churches, and she played the piano while her son took a nap.
Rader pretended to be a telephone repairman to gain entry to the home on September 16, 1986.
After Rader's arrest, her husband and two children released a statement to the media.
"Vicki will never be forgotten," they said. "She touched the lives of so many people and was very special to all of us."
1991: Dolores Davis
Dolores Davis, 62, carried wet wipes everywhere to scrub her grandchildren's faces.
She hid the matches on top of the fridge and would not open her car windows more than a crack in case the children inside were sucked out by a vacuum of air.
She was funny that way, according to her granddaughter, Amy Davis.
"I think about her and I just laugh," Ms Davis told The Wichita Eagle in 2005. "She was the best."
She had been retired for just a few months when she was killed. She was found dead on February 1, 1991.
The case was considered cold until March 2004, when The Wichita Eagle received another letter.
This time the letter included photos and information about the then-unsolved 1986 killing of Vicki Wegerle, along with a copy of her drivers licence.
The return address was sent from Bill Thomas Killman.
Up until then, the death had not been linked to BTK, but just days after parts of the letter were published, police received hundreds of tips from the public.
[arrest archive] More letters followed in the coming months, including puzzles, photos and poems. He also left packages and cereal boxes containing mutilated dolls.
In a letter to police, Rader wrote: "Can I communicate with [a floppy disk] and not be traced to a computer. Be honest."
The police responded via an ad in the newspaper, telling him they could not trace the disk.
A floppy disk was sent to a news station on February 16, 2005.
Rader was arrested less than 10 days later.
New clues uncovered in killer's puzzle
After he started to notice similarities between Cynthia Kinney's disappearance and the BTK killings, Sheriff Eddie Virden made a visit to the prison in El Dorado, Kansas.
"When Dennis came in, the first thing he said is, 'I only killed the 10 people that I'm in here for. So I didn't do whatever you think I did,'" he said.
But after hours of questioning, Sheriff Virden said, Rader asked whether the detective wanted to know one of his favourite fantasies.
"I said, 'Sure, why not?' And he said, 'I always wanted to kidnap a girl from a laundromat.'"
One of Rader's journal entries also referenced a laundromat as a "good place to watch victims". In 2023 detectives dug up the site of his former home in a renewed search for evidence.
Then, just last month — on April 15 — detectives received the word search puzzle in a package from a woman who wished to remain anonymous.
It had been part of a number of items sent to a news station decades earlier.
Some of the words in the puzzle had already been found back in 2004 — including "prowl", "fantasies" and "Wichita".
The names of the 10 known victims and Rader's address were also hidden inside.
After a renewed look, detectives found the words: "Cindy", "Kinney", "laundry mat", and "Pawhuska".
"There's hints all the way through that can't be overlooked," Sheriff Virden said.
"We're still in the process of trying to evaluate that … but it's pretty hard to get around the fact that Cindy Kinney's name is in there."
Another item uncovered by investigators appears to list different US states Rader travelled to and why.
"We have searched many locations," Sheriff Virden said.
"We've found items that we believe are evidence and we've found carvings, markings in barns, things that we believe are 100 per cent proof that he's operated within our area."
Investigations are ongoing and police have said they intend to visit multiple locations potentially connected to both the BTK killings and Cynthia Kinney's disappearance.
Rader 'rotting to his core' in prison
Rader is currently serving 10 consecutive life sentences at the El Dorado Correctional Facility in Kansas, having pleaded guilty in June 2005 to 10 counts of first-degree murder.
His daughter, Kerri Rawson, has told media her 79-year-old father is in a wheelchair and "rotting to his core".
Ms Rawson visited Rader in mid-2023, meeting him face-to-face for the first time in 18 years in an attempt to help investigators get answers.
"[He] wants to live his life out at the prison that he's at," she told NewsNation at the time.
"That's one pressing point. If he's not going to cooperate, then we're going to do this the legit hard way, and he's going to wake up some morning somewhere he doesn't want to be."
