PHOENIX - Prosecutors said Tuesday they will charge Arizona Sheriff Joe Arpaio with criminal contempt of court over immigration patrols.

The announcement was made the day before early voting starts in Sheriff Joe Arpaio’s bid for a seventh term as metro Phoenix’s top law enforcer, his toughest fight yet after more than two decades in office. Arpaio, who calls himself “America’s Toughest Sheriff,” made a name for himself cracking down on illegal immigration and forcing jail inmates to wear pink underwear.

The charges were revealed at a hearing to discuss issues raised by another judge’s request that Arpaio face criminal contempt charges after refusing to stop targeting Latinos in patrols.

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Prosecutor John Keller said in court that the government will bring charges, with the next step being a court filing that’s akin to a criminal complaint.

Arpaio could face up to six months in jail if convicted of misdemeanor contempt. Arpaio has already been found guilty of civil contempt of court in relation the the patrols.

Arpaio has acknowledged violating the order from U.S. District Judge Murray Snow but insists it wasn’t intentional. Snow disagreed, concluding Arpaio knowingly continued the patrols because he believed his immigration enforcement efforts would help his 2012 re-election campaign.

Chad Willems, Arpaio’s campaign manager, said the sheriff doesn’t have anything to worry about with the hearing occurring just before early voting begins.

“It’s more of a procedural matter at this point today. Our efforts and our internal numbers are showing the sheriff is in a very strong position going into early ballots,” Willems said.

Snow also requested criminal charges against Arpaio and his second in command, Jerry Sheridan, for withholding 50 hard drives in a secret investigation that critics say targeted Snow.

The racial profiling lawsuit that Arpaio lost more than three years ago morphed into a contempt case after the sheriff was accused of violating court orders. It revealed deep flaws in Arpaio’s internal investigations, which Snow said had been manipulated to shield sheriff’s officials from accountability.

County taxpayers have shelled out $48 million so far in the profiling case, and the costs are expected to reach $72 million by next summer. That includes $17 million in spending ordered by Snow to make changes to the agency.

Arpaio would face up to six months in jail if convicted of misdemeanor criminal contempt and an unspecified sentencing range if such a conviction is deemed a felony.

A felony contempt conviction would force Arpaio from office, while he could remain sheriff with a misdemeanor conviction. If prosecutors charge him, the case is not expected to be designated as a misdemeanor or felony until later.

Among his many exploits, Arpaio is known nationwide for forcing inmates to wear pink underwear and jailing them in canvas tents during Phoenix’s triple-degree summer heat. He has faced his most crushing legal defeats in the nearly 9-year-old racial profiling case, which focused on his immigration patrols.