We might not know what Banksy looks like, but it's possible we might know what he sounds like thanks to a resurfaced interview which is believed to feature the man himself.

For years now, the elusive graffiti artist has been popping up all over the world and leaving incredible works of art for unsuspecting locals to stumble across.

He obviously travels far and wide and steps out in public to create the work - but still, no one really knows who he is, or what he looks like.

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Is he that guy on the train opposite you, travelling across the country? Or maybe the person behind you at the airport check-in desk? Who knows.

For all we know, Banksy has got his hands on Harry Potter's invisibility cloak in order to get around undetected. It might sound far-fetched, but then you tell me how he's managed to get away with it for so long.

So we might not be able to recognise Banksy's face, but there's a possibility we could identify him through his voice.

The artist mostly communicates with the public via social media now, but in March 2005 he called in for an interview on National Public Radio (NPR), where he seemed to speak with his real voice.

The interview has resurfaced in a 10-episode BBC podcast series called The Banksy Story, and took place as Banksy carried out a series of stunts across famous art institutions in New York, including the Metropolitan Museum of Art.

It features a man speaking in a Southern English accent - but is it too good to be true?

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In the clip, the interviewer says: "We assume that you are who you say you are, but how can we be sure?"

He responds: "Oh, you have no guarantee of that at all."

Though Banksy doesn't confirm his identity, he speaks with knowledge about his work and how he goes unnoticed, and even drops a hint about his appearance.

He explains: "Some of [the pieces] are quite big... Most people let the world go past them and they don't pay a lot of attention to most things - not even, apparently, to people with big beards, wielding around pieces of art and glueing them up."

Banksy suggesting that he has a 'big beard' seems like a good clue about his appearance, but maybe that's just what he wanted listeners to think...

Considering he's gone 18 years since the interview and still hasn't been identified, it's safe to say that any clues he's given still haven't been enough to uncover him. We can keep trying, though!