Image copyright BBC/getty

Atlanta-based rapper 21 Savage has confirmed that he is a British citizen who moved to the US in 1999.

The 26-year-old is still being questioned by immigration officials in America. after he was arrested on 3 February.

Officials say the rapper, whose real name is Shayaa Bin Abraham-Joseph, holds a visa that expired 13 years ago.

For a lot of people, the arrest has come out of the blue and has raised more questions than answers.

Image copyright Instagram/Heatherj4life Image caption 21 Savage's mum shared this post with the caption "The right to choose a better life!"

According to 21 Savage's lawyer - the rapper travelled to America in 1999 when he was seven years-old.

His legal team say that means although his visa expired a year later - it wasn't his fault because he was still a child.

Following his arrest high profile artists like Cardi B, Migos and Nicki Minaj have publicly voiced their support for him.

So far there appear to be more questions than answers since his arrest - hopefully this will help.

1. Where will I have heard his music?

21 Savage is probably best known for his verse on Post Malone's number one single Rockstar. The song has been nominated for two Grammy Awards at the ceremony on 10 February.

Image copyright Getty Images Image caption Cardi B, Drake, Post Malone (l-r) are along the people 21 Savage has worked with

2. He's had his own music out as well right?

Yes. He's a star in his own right though - at the time of writing this article 13.6 million people have watched his latest single A Lot which featuring J Cole.

21 Savage started his career with a crew called Slaughtergang and has gone on to release two solo albums.

The latest, I Am > I Was, features some of the biggest names in the hip hop world including Childish Gambino, Offset from Migos and Travis Scott.

3. Where's his name from?

In 2013, on his 21st birthday, he was shot six times in a drug deal that had gone wrong. His best friend was killed in the shooting.

He also goes by Lil' Man to people who have apparently known him since he was a kid because he was, well, not very tall.

4. What's the confusion?

Image copyright Google Maps Image caption 21 Savage: Atlanta via Newham?

To lots of people 21 Savage is Atlanta through and through.

He regularly refers to Atlanta in his music and has been a key part of the city's rap scene for years.

But now he's been arrested by immigration officials who say he went to the US but failed to leave when his visa expired a year later.

5. Where was he born?

Image copyright ancestry.co.uk Image caption Search results on ancestry.co.uk could only add to the questions

Playing internet detective throws up a range of answers for this one.

He's confirmed he's a British citizen - although Spotify - has gone for "Atlanta-based", while Apple Music lists his "origin" as Dominica the West Indies.

Searching "Shayaa Bin Abraham-Joseph" on ancestry.co.uk doesn't give any results. The records closest to his real name on there relate to "Sheyaa Bin Abraham".

Granted, this may not be 21 Savage but the details match his date of birth and suggest he's from Newham in east London.

And Wikipedia has once again proved itself as an ever-changing source. Until this morning it listed him as being born in the UK, but it's now been changed to "matter of dispute".

6. When did he head to the US?

A statement from 21 Savage's lawyer says he arrived in the US in 1999.

But according to Immigration and Customs Enforcement (ICE) he arrived in the US in 2005. They say his visa expired a year later.

7. Has he ever said he's American?

Image copyright Getty Images Image caption You have to work hard to find a picture of 21 Savage and an American flag

In short, no. In his defence we haven't seen any evidence which suggests so. He's spoken lots about growing up in Atlanta though.

8. How long has be living in Atlanta?

In one interview, he claims he was expelled from Stone Mountain Middle School in Atlanta aged "about 12" for taking a gun to class.

That's the earliest reference he's made directly linked to Atlanta. In that interview he also says he was eight when he first saw a gun but he didn't make it clear where that was.

9. How often has he referred to Atlanta?

His raps have often referred to a violent upbringing in Atlanta surrounded by drugs and guns, so much so that a lot of people have never really felt the need to question where he's from.

10. Why has nobody spotted it before?

American-based think-tank, Center for Migration Studies, claims there are 10.6 million undocumented immigrants live in the US, that's just over 3% of the population.

With no priority system in place, it was always going to take time for potential issues with 21 Savage's paperwork to emerge if there were any.

Although US President Donald Trump has blamed the southern border for illegal immigration, most cases of "undocumented immigrants" are made up of people who overstay their visas - which is what it's claimed the rapper has done.

11. So why now?

A DeKalb County Police Department incident report says the rapper was arrested on Sunday during a traffic stop with another musician, Young Nudy, who is accused of aggravated assault with a gun and gang activity.

Some suggest 21 Savage's lyrics becoming increasingly political and Atlanta hosting the Super Bowl would have brought more attention to him.

However, there has been no indication from officials that this is the case.

12. Has he ever left the US since becoming famous?

He's not referred to time spent outside the US in interviews. The only small mention is a conversation a journalist overheard his manager having when Mexico had been confused with New Mexico for an upcoming show.

13. But hasn't he been on tour?

Image copyright Getty Images

Yes - but interestingly for such a popular artist he's only ever toured in America.

14. Has he ever referred to being British?

In short, no. In the same way that nobody felt the need to question 21 Savage being from Atlanta, there was never really any major reason to question if he was from the UK.

15. Were there any clues?

Image copyright FreddyO/YouTube

During a report from one of the rapper's charity events in Atlanta, a presenter is seen speaking to a women described as "21 Savage mom" who has a VERY British accent.

16. Is this the first time he's been in trouble with the police?

No - in October 2014 he was pulled over and the car he was in reportedly had drugs inside.

17. What do people in Atlanta say?

Again, this news has come as a surprise to everyone.

Lots of people say he's a good ambassador for the city and has put on loads of charity events there.

Speaking to Radio 1 Newsbeat, one local said: "He's a pretty big icon for year who has made it out. He's making great music.

"We're losing someone but I guess he was doing something wrong and he got caught."

18. What are other artists saying?

As you'd expect, the response has been pretty supportive from fellow musicians. Here are a few of the tweets.

19. And everyone else?

We all know the internet can be an unforgiving place...

20. What happens next?

An Immigration and Customs Enforcement (ICE) spokesman said he was being held for removal proceedings. Officials are said to be waiting for a judge's ruling before deciding how to proceed.

21. How could this affect his career?

There're seems to sympathy for him on some level. This is a man who could be up rooted from the family, friends and life he's successfully built.

But rap/hip hop is a genre where authenticity is key. Some fans could be asking "what else don't we know"?

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