Sheriff's Dept. Spokesman RIPS Fiona Apple -- 'Just Shut Up and Sing'

Fiona Apple is an ignorant fool who should stop criticizing law enforcement and "just shut up and sing" ... this according to the spokesman for the Hudspeth County Sheriff's Dept.

HCSD Public Information Officer Rusty Fleming is firing back at the singer after she publicly blasted 4 officers for allegedly mistreating her during her arrest for possession of hash and marijuana at a Texas border patrol stop last week. In a rambling statement at her concert following the bust, Apple had threatened to make the cops "f*cking famous" as a punishment for their inappropriate actions.

Fleming has personally responded to the accusations with a letter to Apple ... and it's AWESOME.

It starts off ... "First, Honey, I’m already more famous than you, I don’t need your help. However, it would appear that you need mine."

The letter continues, "Two weeks ago nobody in the country cared about what you had to say, -- now that you’ve been arrested it appears your entire career has been jump-started. Don’t worry Sweetie, I won’t bill you."

"Next, have you ever heard of Snoop, Willie or Armand Hammer? Maybe if you would read something besides your own press releases, you would have known BEFORE you got here, that if you come to Texas with dope, the cops will take your DOPE away and put YOU in jail."

"Even though you and I only met briefly in the hallway, I don’t know you but I’m sure you’re an awesome and talented young woman and even though I’m not a fan of yours, I am sure there are thousands of them out there, and I’m sure that they would just as soon you get this all behind you and let you go back to what you do best—so my last piece of advice is simple “just shut-up and sing.”

Sincerely
Rusty Fleming"

Rusty called in to "TMZ Live" today where he continued to put Fiona on blast.