Former Rep. John Conyers, a Michigan Democrat who represented the Detroit area for more than 50 years before resigning in 2017, died on Sunday (October 27) at the age of 90.

John Conyers III, the congressman’s son, confirmed the news with CNN. Conyers was a founding member of the Congressional Black Caucus and the longest-serving African American member of the House of Representatives. He was a member of the Judiciary Committee and at one time served as the chairman of the panel.

Conyers was also a civil rights icon who was a major player in the push to establish a national holiday to honor Rev. Martin Luther King Jr.

The Detroit Free Press reports that Conyers died of natural causes.

Born in Detroit in 1929, Conyers was elected to Congress in 1964 and used his position to champion the Civil Rights Movement. In 1994, he worked on the Violence Against Women Act and became the first African American to serve as Chair of the House Judiciary Committee in 2007.

Conyers was also a trailblazer in crafting legislation around reparations for slavery. Beginning in 1989, Conyers introduced a bill at the beginning of each session of Congress that called for a "congressional study of slavery and its lingering effects as well as recommendations for 'appropriate remedies.'"

Rep. Rashida Tlaib, who won Conyers’ district following his retirement in 2017, tweeted Sunday about her admiration for the longtime representative, writing that he "never once wavered in fighting for jobs, justice and peace."

"We always knew where he stood on issues of equality and civil rights in the fight for the people," she said. "Thank you Congressman Conyers for fighting for us for over 50 years."

Famed civil rights activist Rosa Parks worked in Conyers congressional office from 1965 until she retired in 1988.

"For a long time he was Black America's congressman," Sam Riddle, a longtime family friend and consultant to the Conyers family, said Sunday. "On the streets of Detroit, he'll be mourned."

Members of Congress and other politicians also mourned on Twitter. See what some had to say below.

In 2015, John Conyers settled a wrongful dismissal complaint with a female staffer in 2015, after the woman alleged she was fired from his House office after she refused to “succumb to [his] sexual advances.”

Conyers denied the allegations of sexual misconduct, but confirmed that he had paid his former staffer $27,000 as part of the settlement.