A customer spotted something floating in a bottle of Kingfisher Superior Strong Beer that he bought from a foreign liquor shop at New Market on Saturday. When he created a scene, the shop staff replaced the bottle and promised to probe the incident.

"A customer came to our shop on Saturday evening and asked for a bottle of beer," said Nawal Kishore Singh, who helps run the shop of his son, Jitendra Kumar Singh. "One of my employees took out one from the freezer and handed it over to him. Immediately, he started screaming and accusing us of serving him poison, pointing towards the beer. Only then did we realise that the beverage had some light-coloured, thread-like suspended matter."

Nawal quietly replaced the bottle and kept the "contaminated" one inside. He attributed the presence of the foreign material to faulty distillation or something being present in the bottle before it was filled up and sealed.

"The seal of the bottle is intact. I will hand this to the excise department for tests," said Nawal, who is also president of the Patna District Foreign Liquor Retailers' Association.

"Beer manufacturing and bottling is completely mechanised and no manual processes are involved," said Vanshi Dhar, general manager of the manufactured by United Breweries beer manufacturing plant at Naubatpur in Patna district, when asked to comment on the incident. "So chances of any suspended material entering the bottle are negligible. Still, we will look into the matter."

Turns out, a Kingfisher beer bottle was discovered with suspended material at the same shop in February 2015. Assistant commissioner, excise, in Patna Krishna Kumar said: "United Breweries, which makes Kingfisher beer, was fined Rs 1 lakh in the previous case which was brought to our notice."