*Editor's note: This story has been updated throughout.

Texas Gov. Greg Abbott is formally demanding that Travis County Sheriff Sally Hernandez reverse her new policy on cooperation with federal immigration authorities or lose state dollars, further escalating a showdown over "sanctuary cities" that have been in the crosshairs of Republican officials.

"This is not a pronouncement of sound public policy; it is a dangerous game of political Russian roulette — with the lives of Texans at stake," Abbott wrote to Hernandez — whose jurisdiction includes Austin — in a letter dated Monday.

The newly elected sheriff, who campaigned on the issue, announced Friday that her department would reduce its cooperation with federal immigration authorities when they request an inmate be flagged for possible deportation. Her office said it would continue to hold people charged with very serious crimes, such as capital murder.

But that was not enough for Abbott, whose letter calls the policy, which is set to go into effect Feb. 1, "shortsighted" and backed by "frivolous" justifications. He quickly reacted Friday on Twitter, saying that his office "will cut funding for Travis County adopting sanctuary. Stiffer penalties coming."

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Abbott's threat targets Criminal Justice Division grant money that is administered by his office. Travis County got almost $1.8 million from the division over the past year "based upon the commitment that federal immigration law would be enforced," according to the letter.

"Your policy is in violation of that commitment," Abbott told Hernandez. "Unless you reverse your policy prior to its effective date, your unilateral decision will cost the people of Travis County money that was meant to be used to protect them."

In the letter, Abbott also made clear that he intends to make an example out of Hernandez during the 85th Legislative Session that started earlier this month. Abbott is set to lay out his priorities in his State of the State address, which is scheduled for Jan. 31.

"During the pending legislative session, I will be working with the Texas Legislature to do more to protect our citizens from misguided and dangerous sanctuary policies like yours," Abbott told Hernandez. "Your reckless actions endangering the safety of Texans will provide powerful testimony for the need to strengthen Texas law."

This is not the first time Abbott, a Republican, has clashed with a sheriff in a big-city county over immigration policy. In 2015, he threatened to withhold state funds from Dallas County Sheriff Lupe Valdez, a Democrat, after she mades change to her department's detention policy. Valdez, who had said her comments on the policy had been taken out of context, later promised Abbott she would fully participate in federal immigration programs.

"Like his previous harassment of Dallas County Sheriff Lupe Valdez, Governor Greg Abbott's improper attempt to intimidate Sheriff Sally Hernandez is totally unjustified," U.S. Rep. Lloyd Doggett, D-Austin, said in a statement. "The Governor’s interference is not based upon what the law is but what he wants to change it to become in order to satisfy GOP orthodoxy."

Related Tribune coverage:

Travis County sheriff announces new "sanctuary" policy

Six years later, fight over anti-sanctuary cities bill has changed