A director of a computer and mobile-phone repair shop in Wellington says claims, made about it by the right-wing group, Britain First, are "shameful" and "laughable".
The group's leader Paul Golding said a small Islamic symbol fixed to the shop-front showed that it was run by extremists.
The symbol on the sign is the seal of the prophet Muhammed which also appears on the flag of Islamic State, but Wehid Iqbal said he'd been using the emblem long before IS appeared.
Mr Iqbal, who took part in an aid mission to Turkey last year, said the claims had put his staff in danger, but that he had received many messages of support.
Quote Message: "The seal of the prophet is over 1400 years old. I have used it on my numerous businesses for over 13 years and way before the advent of ISIS. For him to come outside the shop to claim my retail outlet is a hotbed of Islamic extremism and a recruitment base for ISIS is totally absurd and laughable. His actions mean that many people who have no interest in actually evaluating what he says and taking it as true has put my staff and business in danger." from Wehid Iqbal Businessman