Mairi Kerin is a blackbelt in karate – and managed to take down the thief in no time (Picture: SWNS) A black belt karate coach managed to send a would-be thief empty-handed from a shop while ...

Without missing a beat, Mairi - a medal-winning Wadokai karate enthusiast, who is also proficient in Brazilian jiu-jitsu and boxing - calmly looked at the man before leaping into action.