José “Cha Cha” Jimenez, a well-known Puerto Rican civil rights leader and founder of the Young Lords organization, has died.

He is 76 years old.

Jimenez died Friday morning, according to his sister, Daisy Rodríguez, who first announced the news in a Facebook post.

In 1968, Jimenez founded the Young Lords organization in Lincoln Park, one of Chicago's poorest neighborhoods. He transformed what was once a Puerto Rican street gang into a political group and community organization modeled on and inspired by the Black Panther Party, according to the Library of Congress.

The Youth Lords advocate for health care, education, affordable housing and jobs. It also spearheads community programs that provide free medical clinics and free breakfasts for children and helps standardize current federal child nutrition programs.

The organization operates a monthly magazine to promote these community services and advance its causes. It also led efforts to create cultural centers to preserve and celebrate the history and heritage of all Puerto Ricans.

While the organization is primarily made up of Puerto Ricans, the Young Lords considers itself a multiracial organization that includes Black, Latinx, women, and LGBTQ members. It also calls itself "revolutionary nationalists" and rallies for Puerto Rican independence.

The Young Lords also oppose police brutality, US imperialism and militarism.

Jimenez was born in Puerto Rico on August 8, 1948, the same month that Black Panther Party leader Fred Hampton was killed in a Chicago police raid at the age of 21.

According to Young Lords member Felipe Luciano, Jimenez's friendship with Hampton sowed the seeds for a broader alliance between blacks, Latinos, whites and other community members committed to civil rights.

Luciano told NBC News in 2021: "He was the one who turned Cha Cha from gang war to organization. They have been long-term friends since then. Cha Cha often talks about it with love and admiration. "

"The rest is history," Luciano said.

Under Jimenez, the Young Lords eventually expanded to New York City and in 1969 joined the Rainbow Coalition—a then-little-known movement that brought together Puerto Rican activists and Confederate flag-waving white Southerners People came together to help address poverty and discrimination under the leadership of the Black Panther Party.

At the time, the alliance shocked some allies and frightened police and the FBI, who feared it would subvert the social order.

Filmmaker Ray Santisteban, who made a documentary about the origins of the Rainbow Coalition and the political groups it joined, said Jimenez was crucial in making the film possible.

Santisteban mourned Jimenez's death on Facebook, writing: "From the first time I met him in 1992 to the last time I saw him, he was focused on uplifting the Puerto Rican community and lives and empowers all the world’s poor.”

Jimenez's family moved to the United States from Puerto Rico when he was an infant, and he lived in Chicago most of his life.

In addition to his work with the Young Lords, Jimenez was the first Latino to announce his candidacy for Chicago City Council in 1974, “to oppose Mayor Richard J. Daley’s gentrification plans and reshape the city’s political landscape and preserve the political power of Puerto Ricans and Latinos,” according to his obituary.

At the time, the Young Lords held a campaign rally that attracted more than 1,500 people, according to the Library of Congress.

Nearly a decade later, Jimenez helped form the first Latino coalition to run on Harold Washington's historic 1983 mayoral campaign. As ward captain, Jimenez mobilized voters to help elect Chicago's first black mayor.

In 1995, Jimenez and other Young Lords members partnered with the Center for Latino Studies at DePaul University to create the Lincoln Park Project to archive and document the organization’s history.

A public funeral for Jimenez will be held Thursday night in Chicago, his family said in a statement on social media.

"As the founding leader and president of the Chicago Young Lords organization, he became one of the most pivotal figures in the civil rights and liberation movements," the family statement read. "He left behind a profound legacy of revolutionary spirit, a vision of Puerto Rican self-determination, and Commitment to justice for the people.”

Jimenez's body will be cremated on Friday and "his final resting place will be next to his mother in Puerto Rico," Rodriguez said.

Jimenez was preceded in death by his parents, Eugenia Rodriguez Flores and Antonio Jimenez Rodriguez, according to his obituary.

Jimenez is survived by his children Jacqueline Jimenez, Sonia Jimenez, Melissa Jimenez, Alejandro Jimenez and Jodette Lozano , as well as his sisters Jeanne, Myrna Jimenez and Rodriguez.