A Miami-Dade fire captain has been demoted down to firefighter as punishment for a rant, posted on his personal Facebook page, about the Trayvon Martin case, county officials said Monday.

Capt. Brian Beckmann’s post lambasted the prosecutor, Angela Corey, who charged George Zimmerman with second-degree murder in Martin’s death.

In the post, Beckmann suggested “urban youth” are the products of “failed, sh--bag, ignorant, pathetic, welfare dependent excuses for parents.”

He also brought his fellow firefighters into the post, saying: “I and my co-workers could rewrite the book on whether our urban youths are victims of racist profiling or products of their failed, sh--bag, ignorant, pathetic, welfare dependent excuses for parents, but like Mrs. Corey, we speak only the truth.”

It ended with, “They’re just misunderstood little church-going angels and the ghetto hoodie look doesn’t have anything to do with why people wonder if they’re about to get jacked by a thug.”

A screen shot of the Facebook page was sent to Miami-Dade Fire Rescue’s human resources department on April 12, according to county records released Monday. A day later, it was published on the website theGrio.com, an African-American news website.

The ensuing investigation found that, though Beckmann’s Facebook page was personal, it hurt the public’s trust in the department, the disciplinary action report said. “While the opinion posted may have been personal, as a captain with Miami-Dade Fire Rescue, it greatly disrupted the public’s confidence in our entire organization as a result of the reference to ‘my co-workers,’ ” it said.

Beckmann will be on administrative leave and must complete a psychological evaluation and diversity training before he returns, said Rowan Taylor, president of the Miami-Dade firefighters union. And when he does come back, it will be at the lower rank of firefighter.

Taylor said an appeal already had been filed. The appeals process will likely take several months.