Prison staff have launched an urgent investigation after a teenager taunted the mother of a schoolboy he murdered in rap videos from his cell.
Marques Walker, now 17, used a smuggled mobile phone to film himself rapping, dancing and smoking at Feltham Young Offender Institution.
He was on remand at the time after stabbing Jermaine Cools, 14, seven times with a zombie knife in Croydon, South London in November 2021.
In the video, Walker can be seen sporting a dressing for a wound he sustained during an altercation in Feltham.
Police were alerted to the footage, which was circulating on social media, by outraged locals after it distressed Jermaine's mother Lorraine Dudek.
The clip was then passed to the judge who sentenced Walker to life at the Old Bailey this week after he pleaded guilty to murder.
The inmate also used the phone to talk to gang associates on the outside and their illicit conversation was saved on messaging app Snapchat.
Walker was a member of Shrublands gang, also known as S-Town, based on Croydon's notorious Shrublands council estate.
In the call, Walker, whose gangland street name is 'Tiny St', is asked if he wants to "say something to everyone" and replies: "Free me now. Free me. F****** free Tiny St."
Walker's voice was was recorded by the friend he was speaking to and was then used on a drill rap video.
Lorraine believes that the aim of the two-minute clip, viewed over 1,000 times on YouTube in the past fortnight alone, was to glorify the murder of her son and taunt her.
The video opens with a shot of the Shrublands Avenue street sign and a map of the estate saying 'Welcome to Shrublands'.
Sinister figures in hoods, balaclavas, masks and gang colours can then be seen roaming the estate and local area.
Jermaine's mother has seen a version of the video and heard Walker's voice saying 'F****** free Tiny St' on it amid the lyrics.
They include: "Mind what you say because this blade will touch you....Wet my blade, that s*** I'm gonna cut you".
The lyrics also mention 'tots', which Lorraine believes is a reference to the killer being prepared to stab children like Jermaine.
Lorraine has also seen another rap video with the lyrics: "Tiny St taped of West Croydon. Really made man go out [killed him], His Marg [mum] upset...", accompanied by emojis of a skull and crying and then two tears of joy emojis.
The film finishes: "%23STown done that. Now he touching clouds", with emojis of a cloud, skull and tears of joy.
In her victim impact statement to the court, Lorraine Dudek said that the family has had to "endure a rap song made and posted online by (Walker's) fellow gang members, goading and taunting us about Jermaine's murder".
No sooner are the videos taken down by police than they are re-posted online with altered lyrics or less obvious references to Jermaine and his family.
In other drill rap lyrics found in Walker's cell while awaiting trial, he mocked Lorraine, saying: "We had mummzy grieving, I left mandem spleeching (bleeding), I had mandem looking at his wounds like shit den I think I'm bleeding".
He added: "Even if that youth was a civilian I would still rewind and chef up [stab] his back'".
Lorraine said of the taunts: "They made me sick to my stomach, laughing, goading, seeking fame out of my son's murder."
A Prison Service spokesperson said: "We are urgently investigating these videos. Phones are not tolerated in prisons or young offender institutions and those who break the rules face tough punishment - including extra days behind bars.
"Our £125million investment in airport-style security has already blocked more than 28,000 attempts to smuggle contraband - including phones - into prisons."
Walker was detained for life with a minimum 19-year tariff in the first televised sentencing of a youth.
Police issued images of the gruesome collection of zombie knives confiscated from him.
A 10in commando knife was found in his rucksack at school in 2020 and Walker, then 15, was given a nine-month referral order.
In 2021, he was twice caught with blades - a 9in hunting knife and 20in zombie knife - but was bailed each time, leaving him free to kill Jermaine outside a chicken shop in Croydon town centre.
The attack was captured on multiple CCTV cameras as Walker plunged the knife seven times into Jermaine's chest, abdomen and shoulder while the schoolboy lay defenceless on the pavement.
Jermaine's parents called for mandatory jail sentences for anyone caught with a knife. Lorraine, 36, said they face a lifetime "existing in pain".
Jermaine's dad Julius Cools, 49, added: "If that boy (Walker) had gone to prison, he would never have killed my son."
While in Feltham, Walker and cons beat an inmate unconscious by raining kicks to his head and stamping on him in an exercise yard.
Walker was heard saying "finish him off" as he was pulled away by guards last July.
Walker boasted as he was being taken back to his cell: "That's how you beat someone up".
The victim required surgery for a brain injury but survived.
