Darius McCrary -- My Son's Paralyzed with Fear ... Claims He's Being Abused

Darius McCrary refused to return his son to his baby mama because he claims the boy has been abused by his stepdad, but he lost the fight and the boy is hysterical with fear.

We're told everything unraveled last week at LAX, when he was putting his 7-year-old boy on a Michigan-bound plane to return to his mom. The boy had a tantrum and cops were called.

According to the police report, McCrary told officers the boy was terrified to return home because his stepfather had physically abused him back in January. Cops then spoke with to the boy and got the same story.

Cops got the message and allowed Darius to leave the airport with his son. The Dept. of Children and Family Services was notified, and that triggered a court battle.

Darius tried to convince an L.A. County judge to award him full custody, but the judge decided the case could only be handled by the Michigan courts and the kid had to be returned to his mom.

So Friday afternoon, Darius met the baby mama at the Hollywood Police Station and handed off their son, who became an emotional wreck.

Darius plans to carry on the fight in Michigan.