U.S. Secretary of the Interior Ryan Zinke talks to reporters before departing Kanab Airport on May 10, 2017 in Kanab, Utah. Zinke has been in the state of Utah since Sunday talking with state and local officials and touring the Bears Ears National Monument.

The nasty back-and-forth underscored both the unusually high number of official investigations facing Zinke , and a previous situation involving Grijalva and a former top staffer on a congressional committee.

Responding to Zinke's tweet, Grijalva said in an email, "The American people know who I'm here to serve, and they know in whose interests I'm acting. They don't know the same about Secretary Zinke."

"It's hard for him to think straight from the bottom of the bottle," Zinke said in a scathing tweet he posted in response to Arizona Democrat Grijalva's op-ed piece in USA Today, which accused Zinke of numerous "ethical and managerial failings" that require him to "resign immediately as Secretary of the Interior."

Embattled Interior Department Secretary Ryan Zinke on Friday angrily lashed out at a congressman who had called on him to resign , saying Rep. Raul Grijalva used tax dollars to pay off a staffer with "hush money to cover up his drunken and hostile behavior."

Zinke or his department have been the subject of "17 publicly known probes" since he took office in 2017, Grijalva noted in his op-ed. Those probes include one, since referred to the Justice Department, into whether he had a conflict of interest in a real estate deal in his native Montana involving a developer who is the chairman of the energy company Halliburton.

His Cabinet position makes him one of the chief regulators overseeing oil and gas drilling activities.

Zinke said during an interview on Fox News on Thursday night that "I'm 10 for 10" in the outcome of investigations into his conduct.

"I've had 10 investigations completed, and you know what they all say? Ryan Zinke followed all the rules, all the regulations, all the procedures. This is politically motivated. In Montana we call it B.S."

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Last December, Grijalva said on a radio show that he signed off on a $48,000 settlement to a former committee staff member who had claimed he was drunk while working. Grijalva, who denied ever being intoxicated on the job, said she had made a complaint of a hostile working environment after he moved to fire her.

"On the advice of House Employment Counsel, I provided a severance package to a former employee who resigned," he said in a statement last year. He also denied having a drinking problem at the time.

His USA Today op-ed Friday said that "Zinke is embroiled in scandals and nepotism," and warned that scrutiny of Zinke by the Natural Resources Committee "will only intensify if I'm chairman" of the committee in the upcoming session of Congress.

In calling for Zinke's resignation, Grijalva wrote, "I take no pleasure in calling for this step, and I have resisted it even as questions have grown about Mr. Zinke's ethical and managerial failings."

"Unfortunately, his conduct in office and President Donald Trump's neglect in setting ethical standards for his own cabinet have made it unavoidable," the congressman wrote.

"While the secretary continues to project confidence, questions have grown since the election about his future plans, and the White House reportedly fears that he would be unable to withstand scrutiny on Capitol Hill," Grijalva wrote. "Those fears are justified. Mr. Zinke has never even tried to offer an explanation for the sheer scope of his well-documented scandals."

The congresman went on to say: "This silence is insulting to the American people, and given the Nov. 6 election results it is unsustainable. Continuing in office as though nothing has changed only shows how little Mr. Zinke has learned over the past year and a half."

"He holds his job as a public trust, not as a stepping stone to his further personal ambitions. He has abused that trust and damaged the Interior Department in the process. The least he can do is step down and give his successor a chance to begin reversing that damage."