A lawyer for Mr Smith has been approached for new comment. A&F declined to comment on the latest developments.
The FBI opened an investigation last year after the BBC revealed claims that Mike Jeffries and his partner sexually exploited and abused men at events they hosted in their New York residences and hotels around the world.
A BBC investigation found there was sophisticated operation involving a middleman and network of recruiters tasked with recruiting men for the events.
Following the BBC’s reporting, a civil lawsuit was filed in New York accusing Mr Jeffries and Mr Smith of sex-trafficking, rape and sexual assault.
The lawsuit also accused Abercrombie & Fitch of having funded a sex-trafficking operation led by its former CEO over the two decades he was in charge.
Under US law, sex trafficking includes getting an adult to travel to another state or country to have sex for money by using force, fraud or coercion.
Confirming the arrest, Brad Edwards of Edwards Henderson, a civil lawyer representing some of the alleged victims, said: "These arrests are a huge first step towards obtaining justice for the many victims who were exploited and abused through this sex-trafficking scheme that operated for many years under the legitimate cover Abercrombie provided.
"The unprecedented reporting of the BBC, coupled with the lawsuit our firm filed detailing the operation, are to credit for these monumental arrests. This was the result of impressive investigative journalism.”
Warning: This story contains descriptions of sexual acts
In its investigation, the BBC spoke to 12 men who described attending or organising events involving sex acts run for Mr Jeffries, 79, and his British partner Mr Smith, 60, between 2009 and 2015.
The eight men who attended the events said they were recruited by a middleman who the BBC identified as James Jacobson.
Mr Jacobson, 70, previously told the BBC in a statement through his lawyer that he took offence at the suggestion of "any coercive, deceptive or forceful behaviour on my part" and had "no knowledge of any such conduct by others".
The BBC also interviewed dozens of other sources, including former household staff.
Some of the men the BBC spoke to said they were misled about the nature of the events or not told sex was involved. Others said they understood the events would be sexual, but not exactly what was expected of them. All were paid.
Several told the BBC the middleman or other recruiters raised the possibility of modelling opportunities with A&F.
David Bradberry, then 23 and an aspiring model, said that it was "made clear" to him that without performing oral sex on Mr Jacobson, he would not be meeting A&F CEO Mr Jeffries.
"It was like he was selling fame. And the price was compliance," Mr Bradberry told the BBC.
Mr Bradberry said he later attended a party at Mr Jeffries's mansion in the Hamptons in Long Island where he met Mr Jeffries and had sex with him.
He said the "secluded" location and presence of Mr Jeffries' personal staff, dressed in A&F uniforms, supervising events meant he "didn't feel safe to say 'no' or 'I don't feel comfortable with this'".
After the BBC’s initial investigation was published last year, A&F announced it was opening an independent investigation into the allegations raised. When we recently asked when this report will be completed - and if the findings would be made public - the company declined to answer.
Like Mr Jeffries and Mr Smith, the brand has been trying to get the civil lawsuit against it dismissed, arguing it had no knowledge of "the supposed sex-trafficking venture" led by its former CEO - which it has been accused of having funded.
Earlier this year, a US court ruled that A&F must cover the cost of Mike Jeffries' legal defence as he continues to fight the civil allegations of sex-trafficking and rape. The judge ruled the allegations were tied to his corporate role after he sued the brand for refusing to pay his legal fees.
The brand said it did not comment on legal matters. However, in its defence submitted to court, A&F said its current leadership team was "previously unaware of" the allegations until the BBC contacted it, adding the company "abhors sexual abuse and condemns the alleged conduct" by Mr Jeffries and others.
In 2014, Mr Jeffries stepped down as CEO following declining sales and left with a retirement package valued at around $25m (£20.5m), according to company filings at the time.
Once one of America's highest-paid CEOs, he was a controversial figure who faced claims of discrimination against staff, concerns about his lavish expenses and complaints about the unofficial influence of his life partner, Matthew Smith, inside A&F.