The teenager arrested by armed police in Holloway Road on Friday over an “explosive device” has been remanded in custody until next month.

Damon Smith, 19, spoke only to confirm his name and address at Westminster Magistrates’ Court this morning.

The London Metropolitan University student entered no plea to a charge of unlawfully and maliciously making or possessing an unspecified explosive substance, with an intent to endanger life or cause serious injury to property, at North Greenwich station on Thursday.

However, defence counsel Simon Eastwood indicated that his client, who has a form of autism, would be pleading not guilty on the grounds that it was a prank.

Dozens of armed police swarmed Holloway Road on Friday afternoon when Smith, of Abbeyfield Road, Southwark, was arrested a day after two members of the public discovered a backpack on a Jubilee line service.

It was handed to the driver, who inspected the backpack and found it contained a suspicious device, prompting the evacuation of North Greenwich Underground station.

A controlled explosion was carried out on the item, which comprised a flask, powder, ball bearings, a clock timing device, a battery and an initiator.

Smith, wearing a baggy grey-green jumper and grey trousers, smiled throughout the 18-minute hearing and waved in the direction of his mother in public gallery.

He was remanded in custody until his next appearance, at the Old Bailey, on November 17.

Additional reporting by PA