"Ali Jr., 44, who confirmed his Muslim faith, was detained about two hours, despite telling officials that he’s Ali’s son and a native-born U.S. citizen, Mancini said."

Being "Ali's son" is nothing special.
And there have been native-born, U.S. citizens, of muslim faith, who have committed terrorism on U.S. soil. They are categorized as "Home-Grown Terrorist".

Feds are were just doing their job.