Woman recalls moment she learned her father was BTK serial killer

When family man Dennis Rader was exposed in 2004 as the notorious BTK killer that had murdered and traumatised the people of Wichita for years, everyone was shocked.

His daughter Kerri didn't suspect a thing until the FBI showed up at her door one day in 2005.

From 1974 to 1991, the BTK killer murdered ten people, including two children.

His self-appointed nickname was an abbreviation for his murder technique: 'Bind. Torture. Kill.'

Dennis Rader was going to be named as the BTK killer eventually, since he regularly taunted the media and police with phone calls and letters detailing his crimes.

For more than a decade, the BTK killer was considered a cold case, with no leads as to who might be the man behind the murders.

That was until 2004 when Dennis decided to spark up the mystery all over again, writing a letter to local paper The Wichita Eagle, claiming that he was also behind the murder of Vicki Wegerle in September 1986 - a case that had previously been unsolved.

Coincidentally, this was exactly the information that authorities needed to name Dennis as the killer.

ABC/Nightline

Recalling the moment that she found out her dad was the man who had terrorised her town for years, Kerri told ABC's Nightline: "There was a knock on my door. He said he was the FBI and then he said: 'Your dad has been arrested as BTK'.

"I was like, 'I think I'm gonna pass out.'"

Even after her dad was publicly named as the BTK strangler, Kerri wasn't sure she could believe it.

She said: "I think reality was starting to creep in and I felt my stomach just twist, realising it could be true."

Kerri's dad had been a nurturing father, he walked her down the aisle at her wedding just the year prior, and now he was suddenly a completely different person.

She said: "We pretty much had the American dream with the three bedroom ranch and the Springer Spaniel dog... it was extremely uncharacteristic of my father to be physically abusive."

ABC/Nightline

She continued: "I had to learn how to grieve the loss of somebody I loved very much, that no one else loved anymore."

Dennis Rader was charged with 10 counts of first degree murder in February 2005.

On his trial date, Rader changed his plea to guilty and showed absolutely no remorse for the murders.

He was given ten life sentences.