Cyclist held up at gunpoint films it on helmet-cam; watch it here

The terrifying moment a gun comes out and a relaxing cycle turns into something very, very different.

Here's a pretty scary clip captured by a young US traveller as he cycled through the streets of Buenos Aires on what appears to be a leisurely sightseeing spin.

But his trip isn't long turning nasty when a man on a motorbike tries to block his path as makes his way down a cyclelane and then pulls out a gun and demands his backpack.

The victim, named online as Alexander Hennessy, clearly gets the fright of his life but manages to get to safety in one piece before the situation escalates.

He was wearing a helmet-mounted camera throughout the whole ordeal and released the footage for you to view, below.

Undoubtedly it was a moment nobody would want to go through, but it makes for some pretty amazing footage.