Squatting low in a black tracksuit and with a flat cap pulled over his eyes, Tyler Robinson looks at first glance like any other teenager.

But to the niche and often dark corners of the internet where Mr Robinson appears to have spent much of his time, the suspect in the Charlie Kirk killing is performing a so-called slouched “Slav squat”.

The pose and the clothes he is wearing in the photo, shared proudly by his mum, form the basis of an internet meme that has long been associated with the far-Right.

While Donald Trump was quick to blame the “lunatic Left” in the wake of the assassination of Kirk on a university campus, a more complex picture of the alleged killer is emerging.

The Slav squat comes from an oft-shared version of Pepe the Frog, the pudgy cartoon toad who has become a calling card for young men on the hard edge of America’s Right.