U.S. Representative Sheila Jackson Lee, a prominent progressive voice in the Democratic Party who was outspoken on African American and women's rights, has died, her family posted on social media platform X late Friday.

Jackson Lee of Texas announced last month she had pancreatic cancer and was undergoing treatment. She was 74, according to media reports.

"The road ahead will not be easy, but I stand in faith that God will strengthen me," said Jackson Lee, the chief deputy whip in the House of Representatives, said in announcing the diagnosis.

"A fierce champion of the people, she was affectionately and simply known as 'Congresswoman' by her constituents in recognition of her near-ubiquitous presence and service to their daily lives for more than 30 years," her family said in the statement.

The 15-term representative, a graduate of Yale College and the University of Virginia Law School, was active throughout her career in promoting legislation aimed at addressing social justice, economic inequality and public health concerns.

Jackson Lee, who represented parts of Houston, introduced a legislation in the House to make "Juneteenth" a federal holiday commemorating the end of the legal enslavement of Black Americans.

The holiday marks the day in 1865 when a Union general informed a group of enslaved people in Texas that they had been made free two years earlier by President Abraham Lincoln's Emancipation Proclamation during the Civil War.

Jackson Lee was a vocal proponent of police reform in the face of Congressional roadblocks after the 2020 police killing of George Floyd, a Black man whose death sparked nationwide protests.

Fellow Democrat Brendan Boyle, ranking member of the House Budget Committee on which she served, called her "a fierce advocate for the people of Houston and for racial and economic justice everywhere." He said in a statement, "The Congresswoman will be truly missed by all of us who served alongside her.”

Jackson Lee also served on the judiciary and homeland security committees.

She received tribute from some Texans at the other end of the political spectrum.

Texas Governor Greg Abbott, a conservative Republican, posted on X that his wife "Cecilia and I will forever remember Congresswoman Sheila Jackson Lee adding that her legacy of public service and dedication to Texas will live on."

U.S. Senator Ted Cruz posted: "I'm deeply saddened by the passing of my friend & colleague Sheila Jackson Lee. She was a tireless advocate for Houston."

She considered leaving Congress in 2023 in a bid to become Houston's first female Black mayor but was defeated in a runoff.

A false claim was used to ridicule her in a widely shared Facebook post in March 2020 that asserted she had said "homicide is the leading cause of murder." Reuters found no evidence she ever made such a statement.