CRUELEST OF

FOR ONE Hispanic ex-firefighter, the FDNY’s heroic reputation has gone up in flames.

Daniel Rivera says he was forced out of the Fire Department by his fellow Bravest — who allegedly used a childhood trauma to cruelly torment the smoke-eater over his tangential link to a years-old discrimination suit.

Now Rivera, formerly of Ladder 35 on the Upper West Side, is filing a discrimination lawsuit of his own.

The defendants include the FDNY and Fire Commissioner Daniel Nigro, along with two lieutenants who allegedly failed to enforce department protocols and a firefighter who led the hate campaign against him, Rivera said.

“I lost something very personal and valuable to me — my career,” said Rivera.

His FDNY buddies-turnedbullies ostracized him at work, left him alone at fires and dredged up old terrors by sadistically filling his gear and locker with roaches, some plastic and some real, he says in the suit.

As a 4-year-old, Rivera was locked inside a dark basement closet where he fell asleep — and awoke covered in roaches.

He was then was doused so heavily in Raid that he suffered chemical burns requiring hospitalization. Decades later, the mere sight of a roach touched off a panic attack, he said.

“There needs to be some real accountability in the FDNY — all the way to the top — about the need for reform,” said the former firefighter, whose papers will be filed Thursday in Brooklyn Federal Court.

Rivera says his two lieutenants didn’t take steps to stop his alleged mistreatment — and when he brought complaints to their superiors and FDNY investigators, it sparked instant retaliation in the firehouse.

“It got so bad, I slept in the gym at the firehouse, I didn’t want to bunk with them out of fear. I’d barricade the door with weights,” he told the Daily News.

For more than 10 years, Rivera says, he enjoyed a stellar FDNY experience, earning rave