On Oct. 21, 2009 in Cole County, Missouri, 15-year-old Alyssa Bustamante strangled a nine-year-old girl, stabbed her and buried her in a shallow grave. Afterward, the killer wrote in her diary, describing the experience: “it’s pretty enjoyable.” This sick lass had listed “killing people” as one of her hobbies on her YouTube page, and prosecutors argued for life imprisonment plus 71 years, accounting for the years lost by her victim. Bustamante pleaded guilty in 2012 to second-degree murder and was sentenced to life in prison with the possibility of parole.

This eight-year old from Bihar, India was convicted in 2007 of the murder of three infants, including a sister and cousin who were both younger than one-year-old. He crushed two of the girls and strangled one, and his family helped him cover up two of the murders. “She was sleeping in the school,” Sada told authorities, describing one of the murders. “I took her a little away, and killed her with a stone and buried her.” In accordance with Indian law, he cannot be charged with murder and is being detained in a children’s home until the age of 18.

This pair of Arkansas middle school students went on a shooting spree at their school in 1998, killing four female students and a teacher. Golden was 11 years old and Johnson was 13 at the time of the massacre, which injured an additional ten people. Both boys were sentenced to prison on multiple murder and manslaughter charges, becoming two of the youngest Americans to face such charges. Each was released on his 21st birthday. Golden has remained a free man, while, in 2008, Johnson was sentenced to 12 years in prison for theft.

This killer was only 14 years old in 1996 when he used guns and bullets to take the lives of his algebra teacher and two classmates at a school in Moses Lake. He wore a trenchcoat and entered the school with two concealed pistols, 78 rounds of ammunition and a high-powered rifle. After shooting his three victims at point-blank range, he also unleashed on others, and later took hostages, which he released after a brief period. He had been diagnosed as suffering from clinical depression and was also taking the prescribed drug Ritalin to deal with his hyperactivity. He is currently serving two mandatory life sentences and an additional 205 years in prison.

In 1961, this precocious poisoner killed his stepmother. She was the young British lad’s first victim, but not his last. Young was 14 years old when he slipped a rare poison in her teacup. She fell ill, but when she died several months later, it was Young’s aunt who turned him into the police. A mental examination followed, and doctors diagnosed him with schizophrenia, among other disorders. They sent Young off to the Broadmoor Hospital, seeking rehabilitation, yet during his stint there he learned more about toxic potions, and alas, killed another poor soul. He killed one more person and poisoned at least 70 others before his death at age 42, in his cell at Parkhurst Prison.

These cold-blooded kids abducted and mutilated the 2-year-old James Bulger in February, 1993 in England. They kidnapped him from a shopping center, tortured him and left him on a rail line more than two miles away where his body was found two days later. Surveillance cameras captured the abduction, in addition to multiple other crimes the killers committed earlier that day. Venables and Thompson were convicted in November 1993, and both were released from prison and granted new identities in 2001. Venables has committed multiple crimes subsequently, including child pornography.

Joshua Phillips, just 14 years old at the time, murdered eight-year-old Maddie Collins in 1998 in Jacksonville, Florida. He beat her head with a baseball bat, stabbed her twice in the throat and stuffed her under his waterbed, where she remained for one week until discovered by Phillips’ mother. Phillips told authorities he panicked after he hit a baseball that struck her in the head as they were playing earlier. Sentenced to life in prison with no possibility of parole, he is 30 years old and remains incarcerated in Hardee Correctional Institution in Florida.

The youngest American ever sentenced to life without parole, Tate was but 12 years old in 1999 when he stomped a six-year-old girl to death in Broward County, Florida. He was practicing moves that he’d seen performed on television by his favorite wrestler, Dwayne “The Rock” Johnson. His mother, a Florida state trooper, described the act as an accidental tragedy. His 2001 conviction was overturned in 2004. But Tate’s days as a free man didn’t last long. In 2008 he pleaded no contest to the robbery of a pizza delivery man and was sentenced to 10 years in prison.

Roughly two months apart in 1968 in England, 11-year-old Mary Bell and accomplice Norma Joyce Bell (no relation) murdered by strangulation a three-year-old and four-year-old boy. She did it purely for the joy of killing, she told the police. The daughter of a dominatrix prostitute, Mary Bell was convicted of manslaughter on December, 1968 and served 12 years in prison. She was released in 1980 and granted a new identity. According to published reports, Bell became a mother in 1984 and a grandmother in 2009, is alive and free today.