WASHINGTON (CN) — Senator Dianne Feinstein, who represented California in the Senate for more than 30 years, has died at 90 years old, her office announced Friday morning.

“Sadly, Senator Feinstein passed away last night at her home in Washington, D.C.,” James Sauls, the senator’s chief of staff, said in a statement. “Her passing is a great loss for so many, from those who loved and cared for her to the people of California that she dedicated her life to serving.”

Feinstein, who recently returned to Washington after a three-month absence while she recovered from a case of shingles, had said in February that she would not seek reelection.

The lawmaker was present for votes Thursday morning, but was conspicuously absent from the Senate Judiciary Committee in the afternoon, where she holds a crucial vote for confirming White House judicial nominees.

Feinstein was first elected to the Senate in a 1992 special election and was the Golden State’s first female senator. Before that, the California Democrat had spent 10 years as mayor of San Francisco.

During her three decades on Capitol Hill — which made her California’s longest-serving senator and the Senate’s longest-serving female lawmaker — Feinstein was a stalwart centrist and an advocate for gun control, leading the charge on 1994’s federal assault weapons ban.

Members of Congress and political figures from both parties offered their condolences Friday morning.

Illinois Democrat Dick Durbin, chair of the Senate Judiciary Committee, called Feinstein a “trailblazer” and said she spent her time in office “fighting for causes that many overlooked.”

“Dianne was my friend and seatmate on the Senate Judiciary Committee for more than twenty years,” Durbin said. “She never backed away from the toughest political battles — she was always dignified and always effective.”

Missouri Republican Josh Hawley said, “It has been an honor to serve with her in the Senate and on the Judiciary Committee. No one was more welcoming when I came to the Senate than she, and no one was a better example.”

California Governor Gavin Newsom said Feinstein was “a political giant, whose tenacity was matched by her grace,” adding that there was “simply nobody who possessed the poise, gravitas, and fierceness of Dianne Feinstein.”

President Biden echoed those sentiments in his own statement Friday morning, calling Feinstein “a pioneering American” and reflecting on his time serving alongside the lawmaker in the Senate for more than a decade.

Los Angeles County Supervisor Kathryn Barger issued a statement on Feinstein’s deaht.

“Dianne Feinstein was a powerhouse if I ever met one. Her depth of knowledge was incomparable, she understood the complexities of every issue. I had the honor of receiving her endorsement when I first ran for L.A. County Fifth District Supervisor in 2016,” said Barger. “Our paths initially crossed when our county’s Department of Health Services was on the brink of collapsing. She was instrumental in working with the Clinton Administration to obtain a waiver for Los Angeles County so that we could direct dollars from our public hospitals to outpatient care. That was a game changer, not only for our county, but for the healthcare industry in general. She will be greatly missed. Senator Feinstein was always a class act.”

Feinstein’s marathon tenure had become a flashpoint for some lawmakers and pundits in recent months, who argued that her extended absence earlier this year cost Democrats a crucial vote in the Senate and hampered President Biden’s policy agenda. Resisting calls to step down, the California senator returned to Washington in May, traversing the halls of the Senate with the aid of a wheelchair.

It wouldn’t be the first time that Feinstein courted controversy over the last several years. The lawmaker received criticism in 2020 for her embrace of Republican Senator Lindsey Graham at the end of a series of confirmation hearings for Supreme Court Justice Amy Coney Barrett.

Feinstein, at that time the ranking member of the Senate Judiciary Committee, said then that the confirmation process was “one of the best set of hearings that I’ve participated in.” Her gratitude towards Graham, then-chairman of the judiciary panel, spurred calls for her to step down as the committee’s top Democrat. Feinstein ultimately voted against Barrett’s nomination.

The lawmaker also drew scrutiny in 2019 after a clip emerged of her dismissing a group of young climate activists.

“I’ve been doing this for 30 years,” Feinstein told the gathered children, who had implored her to support the Green New Deal climate plan. “I know what I’m doing. You come in here and you say it has to be my way or the highway. I don’t respond to that.”

Meanwhile, Senate Democrats could be facing a political bind while Feinstein’s seat remains open — bringing the party’s razor thin majority down to just 50, a figure that includes three Independent lawmakers. Feinstein’s absence on the closely split Senate Judiciary Committee could also complicate attempts to ram through President Biden’s more controversial judicial nominees.

Several of California’s prominent House Democrats are already running for Feinstein’s Senate seat, including Representative Barbara Lee, Congresswoman Katie Porter and Congressman Adam Schiff.

This story was updated by SCVNews.com staff.