Backlash against President-elect Trump’s pick for attorney general mounted this week as civil rights advocates and attorneys from across the country voiced opposition to U.S. Sen. Jeff Sessions (R-AL).

Police arrested six people who participated Tuesday in a peaceful protest at Sessions’ office in Mobile, Alabama. NAACP President and CEO Cornell William Brooks was among those arrested during a staged sit-in that included 30 protesters, according to reporting by AL.com.

Brooks said in a statement that the NAACP opposed the appointment of Sessions, a longtime and staunch adversary of civil rights legislation.

“Senator Sessions has callously ignored the reality of voter suppression but zealously prosecuted innocent civil rights leaders on trumped-up charges of voter fraud,” Brooks said, referring to Sessions’ prosecution of three civil rights leaders who were later acquitted. “As an opponent of the vote, he can’t be trusted to be the chief law enforcement officer for voting rights.”

Bernard Simelton, president of the Alabama Conference of the NAACP, was arrested with Brooks on Tuesday, and has since launched a petition on MoveOn.org to oppose Sessions’ appointment.

“As the highest law enforcement official, the attorney general has the responsibility to protect the civil and human rights of all races, colors and genders,” Simelton wrote. “Senator Sessions is not that person and presents an extreme danger to the equality, diversity and inclusiveness that the U.S. has achieved over the last decade.”

More than 180,000 signatures have been added to the petition as of Thursday afternoon.

Sarah Isgur Flores, spokesperson for Sessions, said in a statement that “many African-American leaders who’ve known him for decades” can vouch for the senator’s long career of upholding the rule of law.

“These false portrayals of Senator Sessions will fail as tired, recycled, hyperbolic charges that have been thoroughly rebuked and discredited,” Flores said.

Sessions is also facing opposition from fellow lawyers. More than 1,100 law professors have a signed a letter urging the Senate Judiciary Committee to reject the Sessions’ nomination, reported USA Today.

The letter cites a 1986 vote by the Republican-controlled Senate Judiciary Committee rejecting President Reagan’s nomination of then-U.S. Attorney Sessions for a federal judgeship. Sessions’ nomination was tanked by his history of racist statements, including reportedly saying he thought the Ku Klux Klan was “OK” until finding out some Klan members used marijuana.

“Nothing in Senator Sessions’ public life since 1986 has convinced us that he is a different man than the 39-year-old attorney who was deemed too racially insensitive to be a federal district court judge,” the law professors’ letter states.

Deval Patrick, former Massachusetts governor and former assistant U.S. attorney general, submitted a letter to the Senate Judiciary Committee opposing the confirmation of Sessions, describing him as “the wrong person to place in charge of our justice system.”

A week before his confirmation hearing, Sessions has been accused of another act of impropriety: burnishing his record on civil rights by falsely claiming involvement in voting rights and desegregation cases.

Sessions in a questionnaire submitted to the Senate Judiciary Committee claimed that he was “personally” involved in litigating four major civil rights cases while he served as U.S. attorney for Alabama. Three civil rights lawyers involved in those cases allege that Sessions “had no substantive involvement in any of them.” In a Washington Post op-ed, the lawyers accuse Sessions of “trying to mislead his Senate colleagues, and the country, into believing he is a champion for civil rights.”

Trump announced Tuesday in a Twitter post that he would have his first press conference as president-elect on January 11, the same day as the Sessions confirmation hearing.