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Jesse Pomeroy -

Jesse Harding Pomeroy murdered at least two people, but his victims are believed to amount to over nine. The crimes included the murder of a four-year-old boy and a 10-year-old girl.

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Jesse Pomeroy -

Jesse Pomeroy was arrested and tried for the murders in 1874, aged 14, becoming the youngest person in Massachusetts to be convicted of first-degree murder. Pomeroy ended up serving his sentence in Charlestown State Prison. He died at Bridgewater State Hospital, aged 72.

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Caril Ann Fugate -

Caril Ann Fugate was 14 when she became the accomplice of spree killer Charles Starkweathe in 1958. Fugate remains the youngest female in US history to have been tried and convicted of first-degree murder.

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Cayetano Santos Godino -

Cayetano Santos Godino, aka El Petiso Orejudo ("The Big-eared Midget"), was a serial killer from Buenos Aires, Argentina. He was nine when he committed his first murder: a three-year-old girl. Godin went on to murder at least another three children.

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Mary Bell -

Mary Flora Bell was just 10 when she killed two boys in Scotswood, Newcastle upon Tyne, in England, in 1968.

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Mary Bell -

On May 25, 1968, Bell strangled to death four-year-old Martin Brown. And then on July 31, 1968, she murdered three-year-old Brian Howe.

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Mary Bell -

The "Tyneside Strangler" was convicted of manslaughter at age 11, making her Britain's youngest female killer. Mary Bell was released from prison at the age of 23.

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Graham Young -

Graham Frederick Young, aka the "Teacup Poisoner" or the "St Albans Poisoner," was an English serial killer who poisoned his victims. At age 14, he was convicted of murdering his father, sister, and a school friend. Young was arrested, but went on to poison more people throughout the years. Graham Young died in his cell in 1990, aged 42.

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Craig Price -

Craig Chandler Price is an American serial killer who was active between the ages of 13 and 15 in Warwick, Rhode Island. Craig Price claimed four victims and remains the youngest serial killer in America. He is currently incarcerated at Florida State Prison.

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Sean Mercer -

On August 22, 2007, 16-year-old Sean Mercer fatally shot 11-year-old Rhys Jones in Liverpool, England. Mercer is currently in prison.

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Alfonza Smalls -

Alfonza Smalls was 14 when, together with Richard Henyard, he killed two sisters (aged three and seven) in Florida, in January 1993.

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Richard Henyard -

Smalls' accomplice, Richard Henyard was 18 at the time, so he was sentenced to death. He was executed in 2008. A minor at the time, Alfonza Smalls was sentenced to life.

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Elmer Wayne Henley -

Elmer Wayne Henley Jr. is a convicted American serial killer best known for participating in the infamous Houston Mass Murders, where numerous teens were tortured and murdered by another serial killer, Dean Corll. Henley was 17 when he shot Corll dead.

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Nathaniel Brazill -

Nathaniel R. Brazill was 13 when he shot dead his schoolteacher Barry Grunow at Lake Worth Middle School in Lake Worth, Florida. In 2000, Brazill was sentenced to 28 years in prison.

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James Bulger -

In 1993, the world was shocked to learn that two-year-old James Patrick Bulger from Kirkby, Merseyside, England, was abducted, tortured, and killed by two young boys.

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Jon Venables and Robert Thompson -

The perpetrators were 10-year-olds Robert Thompson and Jon Venables. The boys were arrested and convicted of murder at age 11, making them the youngest convicted murderers of the 20th century.

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Jon Venables and Robert Thompson -

In this image from surveillance footage, it's possible to see young Bulger being abducted by Venables (holding the victim's hand) and Thompson (above Bulger).

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Jon Venables and Robert Thompson -

They spent time at an undisclosed secure children's home (later known to be the Red Bank secure unit). The boys were eventually released in 2001 and given new identities. Venables, however, was arrested a few more times over the years.

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Lionel Tate -

Lionel Alexander Tate was 13 when he murdered a six-year-old girl in Broward County, Florida. Tate is currently incarcerated.

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Edmund Kemper -

Edmund Emil Kemper III is an American serial killer who murdered ten people between 1964 and 1973.

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Edmund Kemper -

Kemper was 15 when he committed his first murders. He killed both his grandmother and grandfather on August 27, 1964. At the time, court psychiatrists diagnosed Kemper with paranoid schizophrenia. Kemper was then released in 1969.

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Edmund Kemper -

Edmund Kemper went on to commit more murders and was convicted of eight counts of first-degree murder. He was sentenced to eight life prison sentences.

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Rod Ferrell -

Roderrick Justin "Rod" Ferrell was the leader of a teen cult known as the Vampire Clan. The cult leader claimed to be a 500-year-old vampire. In 1996, he brutally murdered a couple in their own home.

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Rod Ferrell -

Aged 17 at the time, Rod Ferrell became the youngest person in Florida on death row. His sentence, however, was reduced to life without parole, a sentence he is still serving.

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Otoya Yamaguchi -

Otoya Yamaguchi was a Japanese right-wing nationalist, who on October 12, 1960, murdered the chairman of the Japan Socialist Party, Inejirō Asanuma.

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Otoya Yamaguchi -

Yamaguchi was 17 when he used a wakizashi short sword to assassinate Asanuma. Otoya Yamaguchi was arrested and took his own life in his cell.

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Steven Washington -

Steven Washington Jr., aka "The Window-Screen Rapist," was a serial killer from Florida. Washington was 15 when he killed three elderly women during home invasions. Steven Washington died in prison in 2004.

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Josh Phillips -

Joshua Earl Patrick Phillips was 14 when he murdered his eight-year-old neighbor, Maddie Clifton, in 1998. Philips is currently serving life imprisonment without parole.

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William Cornick -

William Cornick was 15 when he fatally stabbed his Spanish teacher Ann Maguire at Corpus Christi Catholic College in Halton Moor, Leeds, England. In 2004, Cornick was sentenced to life with a minimum of 20 years, which he's currently serving.

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Willie Francis -

Willie Francis was 16 when he was sentenced to death for killing a pharmacy owner in St. Martinville, Louisiana.

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Willie Francis -

Francis was supposed to be executed by electric chair on May 3, 1946, except he survived. Francis eventually returned to the electric chair on May 9, 1947, and this time the deed was done right.

Sources: (The Mirror) (Life Persona)

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