Hundreds of Irish people have reacted in horror after a pint of Guinness was poured in an "sacrilegious" way in a pub in London.
A picture shared on popular social media page, S**t London Guinness, shows a pint of the black stuff served to a customer in Belushi's, London Bridge.
The iconic drink should be black with a creamy white head and is supposed to be poured in two parts and left to settle to serve it correctly.
However, this pint was served with an extremely large creamy white head, making up almost half of the glass.
Offended Guinness drinkers raged at the "absolute abomination" of a pint, with one person telling the customer to send it back as it looked like an "ice-cream float" rather than a pint of Guinness.
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The wrote: "Send it back, thats an icecream float not a Guinness."
Another tagged his friend, writing: "Check out this absolute abomination"
One woman on Twitter dubbed it a "sacrilege".
And one person thought the atrocious pint pouring was criminal, saying: "The barman should expect a prison term."
However, one man joked: "To play devils advocate, Maybe some people want a half pint in a full pint glass?
According to Fergal Murray, Guinness master brewer and global ambassador, the head on a pint of Guinness should be between 18mm to 20mm, which is around three-quarters of an inch.
The online group, S**t London Guinness, have gained popularity by exclusively sharing pictures of badly-poured pints of Guinness and have a large following with 206,000 followers on Instagram and a further 72,000 on Twitter.
They share pictures of the pitiful pints submitted by their followers from some pints with no creamy head on top, to others poured in the wrong pint glasses.
