Leading up to Arizona's upcoming Democratic primary election on Tuesday, Bernie Sanders held a campaign rally in the Grand Canyon State where he blasted controversial Arizona Sheriff Joe Arpaio as a bully who enforces "un-American and uncivilized" tactics targeting immigrants.

Bernie Takes on Sheriff Arpaio

While speaking to roughly 2,800 people at a Navajo casino Thursday night, the Democratic contender took aim at Arpaio, a long-serving Maricopa County sheriff who is notorious for enforcing aggressive anti-immigrant laws. Arpaio calls himself "America's toughest sheriff" and runs an infamous outdoor "tent city" jail that subjects inmates to extreme heat.

"It's easy for bullies like Sheriff Arpaio to pick on people who have no power. If I am elected president, the president of the United States does have power. So watch out, Joe!" warned the Vermont senator at the rally.

"If elected president, we are going to pass comprehensive immigration reform and a path toward citizenship, whether Mr. Arpaio likes it or not," Sanders added.

At another point during his speech, Sanders told the crowd that the infamous sheriff "ambushed" his wife, Jane, while she was visiting a tent city in Phoenix last week. Apparently, Arpaio showed up unannounced during Jane Sanders' trip and offered her a tour of the tent cities. That's when Jane Sanders seized the opportunity to ask him pointed questions about the jail and immigration enforcement.

"She asked him about racial profiling and he didn't have an answer," Bernie Sanders said. "She asked him about conditions in tent city and other abuses that he has perpetuated, and he didn't have an answer. You know what, he cannot have an answer because what he is doing is un-American and uncivilized."

During his stump speech, Sanders accused Arpaio, who has endorsed GOP front-runner Donald Trump, of picking on children like Katherine Bueno, a 12-year-old girl who watched her undocumented parents get arrested by Arpaio on a TV program three years ago.

Before taking the stage, Bueno introduced the Vermont senator with tears in her eyes and recounted how the image of her father's arrest haunts her every day.

"I want all deportations to stop," she said. "That is why we need Bernie Sanders to be our president."

Arizona's Primary Race

In effort to gain traction among Latinos in Arizona at Thursday's event, Sanders emphasized his promise to create a path toward citizenship. Immigration reform is a hot button issue in Arizona since almost half of all illegal border crossings into the U.S. occur along the state's border with Mexico. Latinos also comprised more than 15 percent of the voting population in the 2008 presidential Democratic primary.

Sanders also released three new television ads on Thursday, featuring Arizona Rep. Raúl Grijalva. In the ads, the Mexican-American rep describes Sanders as an "authentic change agent."

"I support Bernie Sanders for one simple reason: he is authentic. If he gives his word, it is done. The values that Bernie has are the values of this country," Grijalva says in "Valores," a Spanish-language ad. "The values of working hard, the values of equality, the values that everyone has an opportunity. These are American values. The positions that he has in this campaign are the best of any other candidate, Republican or Democrat."

Hillary Clinton Campaigns in Arizona

Hillary Clinton's campaign, on the other hand, will try to boost momentum among Arizona voters this weekend with the help of her husband, former President Bill Clinton. The former president is scheduled to campaign on her behalf Saturday at public events in Phoenix and Tucson.

Watch a clip of Sanders taking shots at Arpaio below.