Security officials at T.F. Green Airport said the weapon, which was disassembled and hidden in three stuffed animals inside a carry-on bag, appeared to be linked to a domestic issue and was not a security threat, WPRI-TV, Providence, reported Tuesday.
The gun and ammunition were spotted Monday when the bag went through an airport X-ray monitor, a Transportation Security Administration official said.
WPRI-TV said the weapons were confiscated and the father and son were allowed to continue on Pinnacle Flight 4036 from Providence to Detroit after questioning.
The incident remained under investigation, WPRI-TV said.