A 17-year-old boy has been charged with attempted murder after a six-year-old boy was allegedly thrown from the viewing platform at Tate Modern in central London.

The teenager was arrested on Sunday afternoon by police responding to reports that a boy had been thrown from the 10th floor of the London art gallery’s Blavatnik extension.

The boy, a French national visiting London with his family, was found on a fifth-floor roof and treated at the scene before being flown to hospital by London’s air ambulance. He remains in a stable, but critical condition and is with his family, who continue to be supported by police officers.

The 17-year-old, who is too young to be named legally, will appear before Bromley youth court at 10am on Tuesday, accused of trying to murder the boy.

Appealing for witnesses on Monday, DCI John Massey said: “It would have been incredibly distressing to watch, and it may be that you left Tate Modern very quickly after. If you have not yet spoken to us about what you saw, please contact us without delay.”

A journalist, Olga Malehevska, was on the viewing platform with her four-year-old son at the time of the incident and described what happened as “absolutely terrifying”.

Tate Modern was the UK’s most popular tourist attraction in 2018, when it was visited 5.9m times, according to the Association of Leading Visitor Attractions.

Anyone with information is asked to contact the Metropolitan police incident room on 0208 721 4868 or @MetCC quoting CAD 4660/4August. You can also contact Crimestoppers anonymously on 0800 555 111.