Dontavious Jackson -- a former star linebacker at Florida State -- says he was called a "f***ing n****r" during an altercation on a flight Wednesday ... and then he claims he was nearly arrested over it all.
Jackson spelled out the disturbing story on his Twitter page late Wednesday night ... saying he was on a United flight when a "racist family" began harassing him.
Jackson claims he was called racial slurs ... but says "flight attendants just let it happen!"
"Unacceptable!!" Jackson wrote of the incident.
But, Dontavious -- who played in 43 games for the Seminoles from 2016 through 2019 -- says when cops arrived to investigate the altercation in Miami, they nearly arrested HIM over it all.
Jackson claims the family "tried to play the victim card, telling the officers I punched/attacked them which was a lie."
Jackson says witness' statements -- and video a person had filmed from the scene on the plane -- was the only reason officers let him go.
"The officer told me if it wasn’t for the witnesses I would’ve been taken to jail," Jackson said. "@united this isn’t right & I’m not staying quiet!"
Jackson later added, "Just grateful to still be a free man smdh."
We've reached out to Jackson and United Airlines for comment, but so far, no word back yet.
Jackson was a solid player for Florida State during his 4-year career ... logging his best season as a junior in 2018, when he tallied 75 total tackles.
The linebacker -- who was one of the best class of 2016 high school recruits in the country -- had hoped to continue his career in the NFL ... but went undrafted and unsigned in 2020.