By MARIA SAPORTA

Coretta Scott King, the widow of Martin Luther King Jr., has died.

The 78-year-old Mrs. King died at a holistic hospital in Rosarito Beach, Mexico, 16 miles south of San Diego, said her sister, Edythe Scott Bagley.

"I was told that she slept away," said Bagley, 81, of Cheney, Pa. "It's comforting. She's at peace now."

A spokesman at Hospital Santa Monica in Rosarito Beach confirmed Mrs. King had died at the health center. He could not say when she had checked in. The center's website says it treats "chronic degenerative diseases considered incurable by the orthodox medical profession."

"It is very difficult for me right now," said Christine King Farris, the sister-in-law of Coretta Scott King. "She was my sister."

Farris said the family is still sorting out details. Farris confirmed that Mrs. King died on the West Coast.

"We will bring her back here," Farris said.

Former United Nations ambassador Andrew Young, a family friend and former King aide, said Mrs. King was found dead by her daughter, Bernice.

"It seemed as though she was resting when she passed away. Bernice thought she had had a rather difficult day yesterday and felt like she needed her rest. It wasn't until early this morning that she [Bernice] went to check on her and saw she had passed away," he said.

"It's just sad to see her gone," said security guard Richard Cheatham. About 7:30 a.m., he had lowered the American flag at the King Center to half-staff.

Last spring, Coretta King was diagnosed with atrial fibrillation, which causes the heart to quiver instead of beat regularly. The condition led to a major stroke and a minor heart attack on Aug. 16. She was trying to recover from the stroke, which impaired her right side and speech, at the time of her death.

Gov. Sonny Perdue ordered flags on all state buildings and grounds at half-staff in memory of Mrs. King. The flags will remain at half staff until sunset the night of her funeral.

"Coretta Scott King was one of the most influential civil rights leaders of our time," said Perdue. "Mrs. King was a gracious and kind woman whose calm, measured words rose above the din of political rhetoric. For decades, she proudly bore the torch of her husband's legacy. Now she has passed it on to a new generation to keep the dream alive. Mary and I mourn the passing of this dynamic leader."

"It 's so significant that we would lose another giant at the heels of losing Ms. Rosa Parks," said the Rev. Harold Middlebrooks, a Knoxville, Tenn., preacher who lived with members of the King family during the Rev. King's student days at Morehouse College and as a civil rights worker.

"Both of them could not be out there on the front lines," he said. "Somebody had to rear the children. That was her role. She saw that that was her role and she did it. At the same time, she was very supportive of her husband."

"I am very saddened by the suddenness of Mrs. King's death," said Evelyn Lowery, president of SCLC/WOMEN. "I am sure that she is much relieved, where she is now. Her last days were not that pleasant.

Lowery said she had seen Mrs. King over the Christmas holidays. The world saw her for the last time in January, when she made a surprise appearance at the King Salute to Greatness dinner.

"She looked so radiant and beautiful. We just hugged and hugged when we saw each other. She couldn't speak, but we were able to communicate," Lowery said. "She was such a strong person. Such a dignified person committed to the movement. She was a leader in her own right."

The Rev. Al Sharpton, a family friend, called Mrs. King's death a "monumental" loss.

" For those of us that were too young to get to know Dr. Martin Luther King, Jr. very well, we got to know Coretta Scott King as a compassionate, caring, yet firm matriarch of the movement for justice. She was kind and gentle with impeccable grace and dignity, yet firm and strong and immovable under issues that she and her husband committed their lives to," said Sharpton.

During the battle to desegregate the South, Coretta Scott King walked alongside her husband. After he was assassinated in April 1968, she stepped out of his shadow and became an internationally respected advocate of justice, peace and human rights.

She worked tirelessly to spread her husband's message of fighting for equality through nonviolent struggle.

Owen Lawson, a manager for Cardinal Health Systems, came to the King Center after hearing the news. He stood for a few moments in silent meditation at the reflecting pool.

"It's not a sad day, not really," said Lawson, a 1992 graduate of Morehouse College. "It's a day to remember Mrs. King and Dr. King and all that they accomplished."

Nickeya Weathers, 29, lives around the corner from the King Center on Auburn Avenue. "I was shocked," Weathers said. "Everybody thought she would get better."

Weathers started crying while standing next to the reflection pool at the center.

"I feel like this was everybody's mother in the fact that her family was so important," she said. "It's just sad."

Said John Evans, who was taking a break from his job at the Parkview Manor Nursing and Rehab Center across Auburn Avenue from the King Center: "Boy, it's really a hurting feeling. My joy just went down when I heard about it because she was such a wonderful person for this community."

Four days after the Nobel Peace Prize winner was killed in Memphis, Coretta Scott King delivered a speech in which she declared, "We must carry on because this is the way he would have wanted it to have been. ... We are going to continue his work."

She spent the next 37 years doing just that.

Staff writers Add Seymour, Bill Montgomery and Ernie Suggs contributed to this report.