Longtime White House journalist Helen Thomas has died at age 92 after a long illness, sources told CNN Saturday.

Thomas covered 10 presidents over nearly half a century, and became a legend in the industry.

She was a fixture at White House news conferences -- sitting front and center late in her career -- where she frequently exasperated government spokesmen with her pointed questions.

Thomas began covering the White House for United Press International when John F. Kennedy became president in 1961 and was a fixture there until her retirement in 2010.

She was a trailblazer and the considered the dean of the White House press corps because she was the longest-serving White House journalist.

Thomas will be buried in Detroit, and a memorial service is planned in Washington in October, according to her family.

President Barack Obama said that it was "not just the length of her tenure, but her fierce belief that our democracy works best when we ask tough questions and hold our leaders to account," that put her in high esteem.

In a written statement, Obama called Thomas a "true pioneer" and said she kept the presidents she covered -- including himself -- on their toes.

Her career, however, came to an end under a cloud of controversy.

Thomas, then working for the media conglomerate Hearst as a syndicated columnist, was blasted for comments she made regarding Jewish people.

In 2010, a YouTube video surfaced showing her saying that Israel should "get the hell out of Palestine," and that the Jewish people should go home to "Poland, Germany ... and America and everywhere else."

Thomas apologized for her remarks, writing, "They do not reflect my heartfelt belief that peace will come to the Middle East only when all parties recognize the need for mutual respect and tolerance. May that day come soon."

She announced her retirement one week later.

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