Men in their 40s and 50s ate at restaurant in Wakayama , Japan , on Friday . They fell ill the next morning with breathing difficulties and vomiting . Health official claimed they asked to eat highly poisonous fish 's liver . Comment: Puffer fish toxins kill - but aficionados eat just enough for tingling on lips .
Men in their 40s and 50s ate at restaurant in Wakayama , Japan , on Friday . They fell ill the next morning with breathing difficulties and vomiting . Health official claimed they asked to eat highly poisonous fish 's liver . Restaurant has been shut down for five days as investigation continues . Puffer fish toxins kill - but aficionados eat just enough for tingling on lips .