It is not completely unheard of from time to time for children to kill. But what is far less common is a child serial killer with multiple victims.
Born in 1998 in the village of Mushahar in Bihar, India, Amarjeet Sada is believed to have murdered three people, including family members, by the time he was eight years old in separate incidents between 2006 and 2007.
The sadistic youth reportedly killed his first victim when he was aged just seven and to date he holds the infamous title of being the world's youngest serial killer.
Little is known about Sada's background but it is understood that he was born into a poor family and his father worked as a labourer.
In 2006 he allegedly murdered his six-year-old cousin, the daughter of his uncle.
It is thought he also killed his own baby sister who was only eight months old.
His last victim was even younger - a six-month old baby girl called Kushboo who lived in the neighbourhood.
Her mother told the police that she had left her child sleeping alone at a primary school while she went off to do some chores.
When she returned her baby was missing and a search was soon launched.
However, a few hours later Sada freely admitted to police that he took Kushboo, hit her with bricks and strangled her to death.
He then led the villagers to where he had attempted to bury her in a nearby field.
According to Sada's uncle, some of his family supposedly knew about the first two killings but were left unreported because they were "family matters".
The police took Sada into custody where he reportedly smiled a lot and showed no remorse after admitting he murdered his sister a few months earlier and his cousin the year before.
One inspector on the case said all the killings were similar in execution.
At the time of his capture, one psychologist called him a "sadist who derives pleasure from inflicting injuries", reports The Sun.
Another said that he has "no sense of right or wrong".
A child cannot be jailed or sentenced to death under Indian law, so Sada was thought to have been detained in a children's home in the town of Munger in Bihar until he was 18.
He is understood to have been released in 2016 and his current whereabouts are unknown.
Other especially young killers across the world include James Fairweather from Essex, who was just 15 when he murdered two victims and was planning another before his arrest.
In America, serial killer Harvey Miguel Robinson, 47, has been on death row since the 1990s for raping and killing three victims in Pennsylvania when he was 17.
Meanwhile Craig Price is the youngest serial killer in US history after stabbing Rebecca Spencer, 27, to death 58 times aged 13 and killing two others by the time he was 15.
