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