By the age of just 17-years-old Gakirah Barnes had built up a feared reputation as one of the most vicious assassins on the streets of Chicago.

The teenager, rumored to have committed her first murder at the age of 14, was reportedly involved in up to 20 gangland deaths, amassing thousands of followers on social media where she spoke about the deaths of friends and gang warfare.

Barnes was known as a 'young killa' and went by the names 'Tyquanassassin' and 'Tookaville'kirah' to the gangs of the city's notorious South Side going on to become one of the most infamous female gang members in US history.

But as she walked to a friend's home in in Woodlawn in April 2014 Barnes was shot dead. She has been hit nine times in the chest, neck and jaw.

The Sun reports that Professor Desmond Patton, who studied Gakirah's online presence, said: 'She almost didn't seem real'

'There was this devilish, monstrous little girl who was going around killing people and that she also talked about on this online,' he added in the documentary.

Gakirah Barnes built up a reputation as one of the most infamous female gang members in US history after amassing thousands of followers on social media

The teenager, rumored to have committed her first murder at the age of 14, was reportedly involved in up to 20 gangland deaths amassing thousands of followers on social media where she spoke about the deaths of friends and gang warfare

Barnes pictured with her friend Raason 'Lil B' Shaw. When he was killed in a chase with police in March 2014 she tweeted: 'Da pain unbearable'. She later added: 'Police took my homie I dedicate my life 2 his revenge 100'

A documentary, Secret Life of a Gang Girl, tells the story of Barnes who has gone on to become immortalized in YouTube memorials and rap videos as 'Lil Snoop', a reference to the fictional 'Snoop' character from TV series The Wire - a cold-blooded killer from the harsh streets of Baltimore.

Barnes, whose own father was shot to death in 1997 when she was less than 12-months old, fell in with a group of young men in her South Side neighborhood of Woodlawn who called themselves the St. Lawrence Boys or the Fly Boy Gang.

Journalist Frank Main told the documentary: 'Her friends started getting shot and I think that she got sucked into gang life and she realized that's where she's going to get respect and honor and the warm fuzzies that other kids get from playing basketball or playing chess or something in high school.'

Although Barnes, who had wanted to be a social worker, was never charged with the murders she is said to have been used by the Gangster Disciples to carry out hits.

Despite her feared reputation her mother Shontell Brown said: 'She just wanted to protect everybody.'

But f ollowing the death of her 15-year-old friend Shondale 'Tooka' Gregory when she was just 13-years-old things took a more sinister turn for Barnes.

Gregory, who was shot as he waited for a bus, was mocked by trolls online who added toilet paper into a picture of him in his casket.

Tyquan Tyler, who Barnes treated like a brother, was killed by a stray bullet in 2012 aged 13

Barnes was almost immediately linked to the death of 20-year-old opposing gang member named Odee Perry, left. Shondale 'Tooka' Gregory, right, was shot as he waited for a bus and was mocked by trolls online who added toilet paper into a picture of him in his casket

Lee Caldwell of Chicago's Gang Safety Team said: 'Essentially, this image started a gang conflict.'

Eight months later, a 20-year-old opposing gang member named Odee Perry was shot and killed.

Barnes was almost immediately linked to the death, with online postings labeling her the 'hitta'.

She was 14-years-old at the time.

Journalist Main added: 'It gave her a giant reputation as a shooter.

'If you are a teenager in a gang in Chicago and you kill somebody, your status rockets.'

The incident saw her infamy rise and she was soon the star of drill rap videos with thousands of followers on Twitter.

Former gang member Angalia Bianca said: 'She was a real badass gangster girl — every bit the definition.

'For females, if you want to keep that kind of respect, she was never going to stop.'

Gakirah Barnes covers her face as she appears in the 'Murda' video in early 2013

At one point Barnes is seen holding an automatic pistol toward the camera in the video

Videos show her pointing guns at the camera and wearing a bandanna to cover her face.

A major turning point for Barnes was the killing of 13-year-old Tyquan Tyler, whose mother had moved him from Chicago to western Illinois to get him away from the city's violence.

Tyler was killed by a stray bullet when two gang members fired into a crowd of youngsters who were leaving a party.

Barnes grieved as if Tyquan had been her little brother and would often refer him as such online.

She adopted the Twitter handle 'Tyquanassassin', writing: 'Tyquan supposed 2 Be hear wit me But instead Lil bro ended up 6 feet under a million miles away. Tyquan left a n--a Wit no heart no feelings.'

The Fly Boy's were also attempting to get the attention of music producers and record labels who had recently taken a huge financial interest in gritty street rap performed by people who were actually 'living' their songs, and not writing about 'thug life' from a condo in Los Angeles.

Keith 'Chief Keef' Cozart, a member of rival gang Black Disciple - the O Block gang - had already been signed by Interscope, moving from the South Side to a mansion in the suburbs and recording songs that derided the Tooka clan.

On April 9, the 30-year-old cousin of Chief Keef, Mario 'Blood Money' Hess, was shot and killed.

Online postings would soon name Barnes, again, as the 'hitta'.

The police did not name her as a suspect, but she posted on Twitter the next day: 'u Nobody until Somebody kill u dats jst real Shyt.'

When her friend Raason 'Lil B' Shaw was killed in a chase with police in March 2014 she tweeted: 'Da pain unbearable.'

She later added: 'Police took my homie I dedicate my life 2 his revenge 100.'

Barnes named her Twitter page 'NO SURRENDER LIL B.'

Blood from Gakirah Barnes' gunshot wounds stain the steps on which she fell in 2014

A hooded gunman approached Barnes 6400 block of South Eberhart Avenue, pictured

This montage of Gakirah 'Lil Snoop' Barnes was circulated on Twitter following her death

On April 10, 2014, the day before her death, she tweeted: 'I Dne seen 2 many of my n****z n a casket…In da end we DIE.'

That same day, a rapper named Lil Jay with the Fly Boy Gang taunted Blood Money's friends by posting a video of himself drinking a red-hued beverage from a Styrofoam cup, singing: 'Sippin' on Blood Money.'

The next day a hooded gunman approached Barnes 6400 block of South Eberhart Avenue, with the blast of bullets sending her falling onto some wooden steps.

'They killed my little ni**a snoop #restuptyqanaassassin,' a Fly Boy Gang associate tweeted.

Reporter Frank Main said at the time: 'The novelty of Gakirah the gang assassin being shot down was huge.

'She was thought to be one of the most notorious shooters in the history of that neighborhood – and she's a girl.'

Professor Desmond Patton, who studied Gakirah's online presence, said: 'She wanted to be the toughest person she could be in that gang.'

Her story was shared as part of documentary Secret Life of a Gang Girl on A&E.