Muhammad Ali's son, who bears the boxing great's name, was detained by immigration officials at a Florida airport and questioned about his ancestry and religion in what amounted to profiling, a family friend has said.

Returning from a Black History Month event in Jamaica, Muhammad Ali Jr and his mother, Khalilah Camacho Ali, were pulled aside and separated from each other while going through the immigration checkpoint on February 7 at Fort Lauderdale-Hollywood International Airport, said Chris Mancini, a family friend and attorney.

Ms Ali was released a short time later after showing a photo of herself with her ex-husband, the former heavyweight boxing champion, Mr Mancini said.

But Mr Ali Jr was not carrying a photo of his world-famous father, who was a recipient of the Presidential Medal of Freedom.

Mr Ali Jr, 44, who confirmed his Muslim faith, was detained for about two hours, despite telling officials that he is Ali's son and a native-born US citizen, Mr Mancini said.

It was the first time Mr Ali Jr and his mother have ever been asked if they are Muslim when re-entering the US, Mr Mancini said.

"From the way they were treated, from what was said to them, they can come up with no other rational explanation except they fell into a profiling program run by customs, which is designed to obtain information from anyone who says they're a Muslim," Mr Mancini said.

"It's quite clear that what triggered his detention was his Arabic name and his religion."

US Customs and Border Protection released a statement on Friday saying it could not discuss individual travellers, but did speak more broadly about inspections.

"All international travellers arriving in the US are subject to CBP inspection," The Courier-Journal's report about the detention said.

An airport spokesman referred questions to customs and border protection officials.

The news of Mr Ali Jr's detention comes after best-selling Australian children's author Mem Fox was detained by immigration officials at LA Airport earlier this month.

She said she felt like she had been "physically assaulted" and "sobbed like a baby" in her hotel room after the questioning.

Alis considering filing federal lawsuit

During his detention, Mr Ali Jr was repeatedly asked about his lineage and his name, "as if that was a pre-programmed question that was part of a profile," Mr Mancini said.

Mr Ali Jr and his mother have been frequent global travellers. The family connects their treatment to President Donald Trump's efforts to restrict immigration after calling during his campaign for a ban on Muslims entering the US.

"This has never happened to them before," Mr Mancini said.

"They're asked specifically about their Arabic names. Where they got their names from and whether they're Muslims. It doesn't take much to connect those dots to what Trump is doing."

Ms Ali and Mr Ali Jr live in Florida. They have not travelled abroad since, and are considering filing a federal lawsuit, Mr Mancini said.

Ali, the three-time heavyweight champion and humanitarian, died last June at age 74 after a long battle with Parkinson's disease.

People lined the streets of Louisville, Kentucky, to say goodbye to the city's most celebrated son before a star-studded memorial service watched worldwide.

Syrian cinematographer barred from attending Oscars

Meanwhile, US immigration authorities are barring entry to a 21-year-old Syrian cinematographer who worked on a harrowing film about his nation's civil war, The White Helmets, which has been nominated for an Academy Award.

According to internal Trump administration correspondence, the Department of Homeland Security decided at the last minute to block Khaled Khateeb from traveling to Los Angeles for the Oscars.

Mr Khateeb was scheduled to arrive in Los Angeles on Saturday, travelling on a Turkish Airlines flight departing from Istanbul.

But his plans have been upended after US officials reported finding "derogatory information" regarding Mr Khateeb.

White Helmets focuses on the rescue workers who risk their lives to save Syrians affected by civil war ( AP: Netflix )

Derogatory information is a broad category that can include anything from terror connections to passport irregularities.

Asked for comment, a spokeswoman for the Department of Homeland Security, Gillian Christensen, said, "a valid travel document is required for travel to the United States".

The White Helmets, a 40-minute Netflix documentary, has been nominated for Best Documentary Short.

AP