Gwen Ifill, a co-host of the long-running “PBS NewsHour” and a noted debate moderator, has died following a battle with cancer. She was 61.

“It is with extremely heavy hearts that we must share that our dear friend and beloved colleague Gwen Ifill passed away this afternoon following several months of cancer treatment,” a statement from “PBS NewsHour” read. “She was surrounded by loving family and many friends whom we ask that you keep in your thoughts and prayers.”

Paula Kerger, PBS’s president and CEO, celebrated Ifill’s career in her own statement.

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“Gwen was one of America’s leading lights in journalism and a fundamental reason public media is considered a trusted window on the world by audiences across the nation,” Kerger said. “Her contributions to thoughtful reporting and civic discourse simply cannot be overstated. She often said that her job was to bring light rather than heat to issues of importance to our society. Gwen did this with grace and a steadfast commitment to excellence.”

Sara Just, executive producer for “PBS NewsHour” alerted staff to the news in an email Monday.

“Gwen was a standard bearer for courage, fairness and integrity in an industry going through seismic change. She was a mentor to so many across the industry and her professionalism was respected across the political spectrum. She was a journalist’s journalist and set an example for all around her,” Just wrote in her message.

“So many people in the audience felt that they knew and adored her. She had a tremendous combination of warmth and authority. She was stopped on the street routinely by people who just wanted to give her a hug and considered her a friend after years of seeing her on TV. We will forever miss her terribly.”

CBS News’ “Face The Nation” anchor John Dickerson wrote a tribute to his friend and colleague, which can be read in full here.

“Gwen’s smile. It was so strong it greeted you before you met her. You could read by the light of her smile. And if you could make her laugh that was a prize. The sound of pure joy,” Dickerson said. “We were lucky, those of us who knew Gwen because we spent time in her company, but also because we have her example.”

New York native Ifill graduated from Simmons College in 1977 and went on to hold positions at The Washington Post, The New York Times and NBC before joining PBS’s “Washington Week in Review” in 1999.

Perhaps best known nationally for her work as a debate moderator, Ifill moderated the 2004 and 2008 vice-presidential debates that pitted Dick Cheney against John Edwards and Joe Biden against Sarah Palin. Ifill also moderated a Democratic primary debate between Bernie Sanders and Hillary Clinton.

Reactions to Ifill’s passing and tributes to her work began hitting social media Monday afternoon.

We mourn the loss of an outstanding and beloved journalist and friend. Gwen Ifill will be deeply missed. — John Lewis (@repjohnlewis) November 14, 2016

Howlingly sad. Dear sweet Gwen is gone. RIP @gwenifill — John Dickerson (@jdickerson) November 14, 2016

Oh my heart is breaking. Love you and miss you @gwenifill RIP — Soledad O'Brien (@soledadobrien) November 14, 2016

.@gwenifill I'm heartbroken and not ready for the past tense with you. Sending all the love in the world to your family and loved ones. — Lin-Manuel Miranda (@Lin_Manuel) November 14, 2016

Heartbroken to learn Gwen Ifill has passed away. She was my hero, a woman who deserved all the praise she received. Honest and true — Tamron Hall (@tamronhall) November 14, 2016

With deep and profound sadness. My friend, -- the @NewsHour anchor @gwenifill has gone on to glory. We will miss her voice, her works & more — Donna Brazile (@donnabrazile) November 14, 2016