Shayaa Bin Abraham-Joseph, 26, came to America in July 2005 aged 12 and failed to leave when his visa expired a year later, US officials say.

Immigration and Customs Enforcement (ICE) also say the musician is a convicted felon.

His lawyer accused the US of trying to "intimidate" the rapper into leaving.

What did the lawyer say?

Attorney Charles Kuck said in a statement on Monday that the arrest was "based upon incorrect information about prior criminal charges" and that his client had never tried to conceal his immigration status from authorities.

In 2017, he applied for a US "U Visa" on the basis that he had been the "victim of crime", his lawyer said.

U Visas are given to non-citizen victims of crime who intend to co-operate with US authorities.

In 2013, the rapper was shot six times on his 21st birthday in an attack that took the life of his best friend.

Mr Kuck added the rapper is "not a flight risk" and is a "prominent member of the music industry" who would be recognised if he attempted to flee.

The lawyer said the rapper also has US-born children, which Mr Kuck argued should prevent his client's deportation.

"ICE has not charged Mr Abraham-Joseph with any crime," Mr Kuck continued.

"As a minor, his family overstayed their work visas, and he, like almost two million other children, was left without legal status through no fault of his own."

The lawyer accused US immigration officials of trying to "unnecessarily punish him and try to intimidate him into giving up his right to fight to remain in the United States".

Mr Kuck said his client was "clearly not a danger to the community" and is "the type of immigrant we want in America".

What do US and UK officials say?

A DeKalb County Police Department incident report says the rapper was arrested on Sunday during a traffic stop.

Mr Abraham-Joseph was detained by the US Bureau of Alcohol, Tobacco, Firearms and Explosives, a federal law enforcement agency.

A fellow musician, Quantavious Thomas, known as Young Nudy, was also arrested during the traffic stop.

Mr Thomas is accused of aggravated assault with a gun and participation in criminal street gang activity.

According to ICE, Mr Abraham-Joseph was convicted of drug charges in 2014 and his arrest on Sunday was a "targeted operation".

An ICE spokesman added that when the rapper was first arrested, ICE was not aware of his immigration status.

"His whole public persona is false," said an ICE agent, adding that his childhood was not actually spent in the US.

The UK Foreign Office told BBC News: "Our staff are in contact with the lawyer of a British man following his detention in the USA."

Who is 21 Savage?

Previous to his arrest by immigration officials, Abraham-Joseph has described a childhood in Atlanta, Georgia, not the UK.

In an interview with Fader magazine in 2016 he said he had first seen a gun at the age of eight - though the article did not specify where this purported incident took place.

The musician is also quoted as saying he was expelled from school in Atlanta aged about 12 or 13 for taking a gun to class.

His music has drawn controversy at times, with the rapper apologising last December for a lyric on his second album that referenced "Jewish money".

But since finding fame, 21 Savage has contributed to financial literacy programmes with underprivileged youth.

A fan in Atlanta told the BBC: "He's an icon for here. He's making great music. We're losing someone big."