Jonty Bravery, 18, was sentenced after being found guilty of attempted murder at London’s Old Bailey.

The court was told that Bravery spent more than 15 minutes stalking potential victims at the tourist attraction.

The Old Bailey heard that Bravery, who was 17 at the time of the incident in August, “scooped [the victim] up and, without any hesitation, carried him straight to the railings and threw him over”.

The boy “fell head-first towards the ground,” landing on a fifth-floor balcony below and suffered a bleed to the brain and has been left with life-changing injuries requiring round-the-clock care until at least 2022.

Bravery is said to have “smiled and shrugged” after the incident.

The victim was visiting London from France and had been skipping ahead of his family along the platform towards Bravery, before he threw him off the balcony.

Prosecutor Deanna Heer said the boy, who cannot be identified for legal reasons, still requires round-the-clock care and is lucky to have survived.

She told the court: “CCTV also shows the defendant backing away from the railings, he can be seen to be smiling.

“He has his arms raised and appears to shrug and laugh. CCTV also captured the parents in disbelief and rising panic.”

Mrs Justice McGowan said Bravery intended to kill and “almost killed that six-year-old boy”.

While sentencing, the judge said: “That little boy has suffered permanent and life-changing injury.

“You went to the viewing platform, looked around and spotted the victim and his family and went to the boy and threw him over the railing.

“The fear he must have experienced and the horror his parents felt are beyond imagination.

“What you did on the day of this offence prove you are a grave danger to the public. You planned this and appeared to revel in the notoriety.”

In a victim impact statement from February, the boy’s parents, who have returned to France with their son said: “Words cannot express the horror and fear his actions have brought up on us and our son who now, six months on, is wondering why he’s in hospital.

“How can he not see in every stranger a potential ‘villain’ who could cause him immense pain and suffering?”