A Delta Airlines passenger traveling from Minnesota to Georgia faces federal assault charges after allegedly slapping a fellow passenger's toddler son for crying during the flight.

Joe Rickey Handley of Idaho was on Flight 721, set to land at Hartsfield-Jackson International Airport in Atlanta on Feb. 8, according to an FBI court affidavit. He was sitting next to Jessica Bennett and her 2-year-old son, who began crying as the plane started to descend.

Bennett, who was seated in row 28 alongside Handley, told FBI agents that she tried to get her son to stop crying when Handley "told her to shut that ['N word'] baby up."

"Ms. Bennett stated that Joe Rickey Handley then turned around and slapped [the baby] in the face with an open hand, which caused the juvenile victim to scream even louder," court documents said.

The 33-year-old Minneapolis mother said the slap caused a scratch below her son's right eye.

That's when fellow travelers stepped in.

"After Joe Rickey Handley struck [the child], Ms. Bennett received assistance from several people on the plane, including male passenger Todd Wooten," court documents said.

Wooten, who was seated in row 16, said he heard derogatory language coming from the rear of the aircraft and witnessed Handley slapping the child.

"Let's just let the case speak for itself as it develops," Atlanta Federal Criminal Defense Attorney Marcia Shein said.

Shein, who's representing Handley, said her client will be pleading not guilty.

Efforts to reach Bennett and Handley by ABC News were unsuccessful.