ATLANTA — A confessed serial killer's story appears to have some holes in it.
11Alive first broke the story that Nicholas Gibson says he committed his first murder when he was a 12-year-old in Cobb County.
Gibson, who is a suspect in a gruesome murder in Miami, told investigators he killed a homeless man with a brick. Investigators in Cobb County's Cold Case Unit say they don't have any cases that match the description of Gibson's confession.
Another reported confession also doesn't add up.
The Daily Mail is reporting that Gibson confessed to drowning a woman in Florida in February of 2015. But jail records obtained by 11Alive show Gibson was actually in a Georgia prison at the time of that death.
Gibson's backstory remains a mystery.
His jail records from four different states show he's been behind bars for most of the last 20 years.
Gibson was first convicted of rape in 2000, when he was just 12. He was sent to a juvenile detention center in Harrisburg, Illinois. He was released in August of 2007.
Just four months later, Gibson found himself back behind bars. He spent four years in a Pennsylvania prison for statutory rape. Authorities say the then-21-year-old had a relationship with a 15-year-old girl.
He left prison in June of 2012 and moved to Cobb County. Once again, just a few months later, he was in trouble with the law again.
Gibson was arrested in September of 2012 for failing to register as a sex offender. Federal records show Gibson skipped bond and disappeared.
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He was arrested in Miami in February of 2013. After a short stint in a Florida prison, Gibson was extradited back to Georgia.
After getting out of the Autry State Prison in October of that year, Gibson was arrested a month later for - once again - failing to register as a sex offender.
Gibson was released from Dooly State Prison in November of 2015. He moved to Florida where he stayed out of jail for about a year-and-a-half.
But, in March of 2017, Gibson was arrested again for failing to register as a sex offender. He was released in November of 2018.
In the last 20 years, Gibson has only been out of jail for about 35 months.
Right now, he's only a suspect in one murder - a gruesome killing with a sword in Miami Beach. Investigators in Georgia, meanwhile, are still looking into his claims.