Yuya Motomura, a 45-year-old mahjong parlour manager in Japan, is one of a handful of Japanese men who have joined Ukrainians battling the Russian invasion, bucking a decades-long national principle of pacifism and their government's own warnings.

"People in this town (in Japan) probably see me as a punk, someone rogue, but I've always felt that I'm someone who is more socially conscious than other people realise," he says.