Mongrel Mob has nothing on Latin American gangs - Ross Kemp

Extreme World documentary-maker Ross Kemp says he doesn't believe New Zealand's gangs are "on a par" with others around the world.

The former EastEnders actor has been travelling the globe for nearly two decades, telling stories about the world's most dangerous people and places.

In 2005, he visited the Mongrel Mob while filming here.

Kemp told NZME last year he "didn't have a particularly awful time" when he visited the gang back then, and even got to "sit in [a gang member's] house, have dinner with his wife and get to know his kids".

Speaking to The AM Show on Friday morning, the BAFTA-winning journalist explained the gang culture here simply doesn't compare to that of Latin America.

"I don't think [the Mongrel Mob] is on a par with MS-13 or 18th Street in El Salvador," he said.

"Ten percent of the population of El Salvador is involved in a gang, and when they come and knock on your door and ask you to join when you're 10 years-old, if you don't they'll shoot your mother."

Kemp says gangs in Central and South America "can't be controlled".

He also describes covering them as challenging in a number of ways. Kemp says he's had to be careful not to be coerced into acting as a PR agent communicating the gang's agenda.

"You have to understand when you are being used as a platform for them, and that can definitely happen with terrorists," he said.

Another difficulty with gangs is winning their trust, he says, and that can come in many different forms.

"I was set fire to and shot across the finger by some Russian Nazis. I'm not sure why we have Russian Nazis, but we do," he said.

"We've been cavity-searched getting into certain prisons - and they've not used rubber gloves, they've used plastic bags from across the way."

But despite all he's seen, Kemp still has "total" faith in humanity.

"It's not about the total negativity of who we are, it's about all the things that bond us and divide us - and eventually, overwhelmingly, I think we're good," he explained.

"Obviously we concentrate on the people that aren't so good, but a lot of people are victims of circumstance and you have to understand the environments they come from."

Kemp is currently in New Zealand ahead of his new show Extreme Tales Live on Stage, which will give an insight into the making of his documentaries, and what he's learned from the experience.

"This is a show about everything," he said.

"We're talking about the things that divide us - poverty, ignorance, greed, religion - and all the things that unite us, that I've found over 17 years."