Islamic extremists have turned several areas in US cities into "no-go areas" areas for non-Muslims, according to National Rifle Association (NRA) speaker Steve Tarani.

Tarani, a security and personal safety expert, told a crowd at the NRA convention in Nashville, Tennessee, how he had seen "with my own eyes" how there are areas in the US where even police cannot enter because they are controlled by Islamic "settlements".

Tarani, described as an "internationally respected" edged weapons and personal safety expert, said he witnessed these "no-go" areas with a friend who serves in the Detroit Metro SWAT Police while on patrol through the town of Dearborn, Michigan.

He said during the NRA's annual meeting: "The street signs suddenly went from English to Arabic. There wasn't a single English word on any shop or any street sign.

"In fact, these little yellow signs were posted all along the edges. Jeremy said to me, 'This is it. We don't go past this line.' And I said to Jeremy, 'What do you mean? You guys are Detroit Metro. You're the SWAT team. You can go anywhere you want. What if you get a call over there?' He said 'This is it, it's hazardous for our team if we go past this line,'" reported Think Progress.

Steve Tarani added: "Dearborn, Michigan is not the only place that these settlements exist. They are spread out over the country in various cities. There's an estimate of over 5,000 known terrorist cells in the United States. However, our most persistent and significant threat, right now, to us here today this morning, is the home-grown violent extremists.

"It's possible that at least 20% of what comes over that border — that's a big number, guys — is Hamas, the Muslim Brotherhood, the Ethiopian al-Shabaab, known gang members and supporters of the cartel."

Al-Shabaab are an Islamic militant group based in Somalia, not Ethiopian as described by Tarani.

Earlier in 2015, Jack O'Reilly, the mayor of Dearborn – a town in which around 30% of its population of 95,000 are of Arab descent – dismissed suggestions that parts of the town operate "no-go" areas.

"The people who perpetuate it use it for their own gain," O'Reilly told the Daily Beast. "There are certain sites and individuals who like to perpetuate fear of Muslims - the people who like to suggest Muslims shouldn't remain in the US."

Fox News were forced to apologise in January 2015 for a broadcast which described Birmingham, the second biggest city in the UK, as a "totally Muslim" city where "non-Muslims simply don't go in".

Terrorism commentator Steve Emerson was widely mocked for the claims, with even Prime Minister David Cameron describing him as a "complete idiot".

Emerson later apologised for "having made this comment about the beautiful city" and donated £500 to a children's hospital in Birmingham.

Paris also filed a lawsuit against Fox News after frequently perpetuating the myth there are "no-go" areas in the French capital in the wake of the Charlie Hebdo massacre. The US broadcaster even aired a map which claimed to outline where these areas are before later admitting there are no "formal designation of these zones".