Pics shows: A Jack Daniels flag; A man who displayed a Jack Daniels flag outside his house was mistaken for a terrorist after neighbours thought the black bourbon logo was that of the so-called Islamic State. A 29-year-old man with an Italian background decided to put a flag of the American whiskey brand Jack Daniels on a flagpole outside his house in Zurich, Switzerland's biggest city. The man, who wished to remain anonymous, said: "I hung it up, because I found it funny." But ostensibly, the joke was completely lost on his neighbours who mistook the famous logo of the Tennessee distiller for the black-and-white IS flag. When the 29-year-old man got home on Saturday and emptied his letterbox, he found an anonymous letter. It read: "Should we be afraid of you? First the Italian flag and now the black flag of death." The letter was signed by "concerned neighbours", who according to local media wrote they would put the man and his girlfriend under watch. He said: "I was completely flabbergasted when I read it." The man said he does not know who exactly wrote the letter. He said: "I talked to the neighbours but no-one knows anything about it. "We want to address the responsible person or persons." The man said that as soon as he finds out who is behind it, he might take legal steps. He said: "When it is wrongly told that we are supporters of IS, it is defamation." Removing the Jack Daniels flag is completely out of the question, according to the man, as "then we would prove them right". The Zurich cantonal police said that in such cases after receiving an anonymous note it is recommended to inform the police.