The 28-year-old, who signed with the Chargers in 2022 after spending his first three seasons in the NFL with the Rams, said the incident all happened at John Wayne Airport in Orange County, Calif.

He claims as he was going through security checkpoints, an agent touched him inappropriately. He alleges that when he asked the worker to stop -- he was then "swarmed" by three more TSA members.

"I'm all for people doing their job well," he wrote in a series of statements on his Twitter page Friday morning. "But it was extremely unnecessary and dehumanizing. I travel a lot, for personal and work reasons. I’ve never experienced anything like that @JohnWayneAir."

Joseph-Day says he immediately went to file a complaint ... but accused officials of "making me jump through hoops to do so."

"I'm not sharing this on Twitter for sympathy. I'm sharing this so this group of gentleman and staff aren't allowed to do this ever again to another human being."

TSA released a statement to Fox News on the matter on Sunday ... saying it was aware of the allegations and is investigating the claims.

"We are looking into the matter to determine if our procedures were followed and whether any corrective action needs to be taken," officials said.

"TSA remains committed to treating every traveler with dignity and respect while carrying out its security screening responsibilities."