Thai police have arrested a Japanese yakuza boss on the run for 15 years after pictures of his tattoos went viral on Facebook.

Shigeharu Shirai is accused of murdering a gang rival in 2003. The photographs of the 74-year old fugitive’s elaborate yakuza tattoos were taken by a local person in Thailand unaware of his identity.

The mafia-like yakuza gangs have been part of Japanese society for centuries and have an estimated 60,000 members.

While the gangs themselves are not illegal, much of their earnings are gained illicitly through gambling, prostitution, drug trafficking and cyber-hacking.

When the pictures of Mr Shirai went viral they caught the attention of Japanese police who requested his arrest.

Police detained him in the town of Lopburi, north of Bangkok, for visa violations and he will be extradited to Japan to face the murder charges.

According to Thai police, he admitted he was a member of a yakuza gang but did not confess to the 2003 murder. He fled Japan for Thailand in 2005.

The Facebook pictures show an old and frail-looking man with his entire back and most of his chest covered in tattoos. He is seen playing a board game with other retirees by the side of the road. Pictures also show that he is missing part of his little finger, often a self-administered punishment for members of Japan’s yakuza gangs to atone for mistakes.