A file picture taken on May 18, 1988 in Paris shows US singer Whitney Houston performing at the POPB (Bercy hall). Grammy-winning pop legend and actress Whitney Houston, 48, was found dead on February 11, 2012 in a Beverly Hills hotel, police said. AFP PHOTO BERTRAND GUAY (Photo credit should read BERTRAND GUAY/AFP/Getty Images)
LOS ANGELES (CNN) -- As the the music industry prepared to pay tribute to Whitney Houston at the Grammy Awards Sunday night, the world awaited answers about the last moments of the pop superstar's life.
Houston, whose soaring voice and enormous talent were overshadowed in recent years by her battles with drug addiction, was found dead Saturday in a Beverly Hills, California, hotel, hours before she was to attend a pre-Grammy party hosted by the songstress' longtime mentor, Clive Davis. She was 48.
Still, questions persisted about the circumstances surrounding her death. Police and fire officials were called to her room at 3:43 p.m. Saturday after her bodyguard found her unconscious body.
Houston was found in the bathtub of the room, hotel employees and people close to Houston told entertainment news website TMZ. Pill bottles were found at the scene, TMZ reported, citing "informed sources."
The bodyguard attempted CPR on Houston, sources close to her told TMZ.
There were "no obvious signs of criminal intent," said Beverly Hills Police Lt. Mark Rosen. An autopsy is scheduled.
CNN could not immediately confirm the TMZ reports Sunday.
Police were tight-lipped about the investigation Sunday, saying no updates would be forthcoming until Monday.
Officers were no longer at the hotel Sunday, said Beverly Hills watch commander Donald Chase, but would not say whether that meant the on-site investigation was complete.
Houston's battles with drugs had long made headlines, but she was in the midst of a comeback, with a few shows scheduled and a movie in the works.
Fans: Houston's music spanned an era
A music industry executive, who recalled hearing two loud booms from the room below hers -- the room where, she later learned, Houston had died -- said she had seen Houston and her daughter, Bobbi Kristina, swimming in the hotel pool days before.
The two looked happy, she recalled, and Houston seemed healthy and beautiful. However, it remained unknown whether the singer had won her battle with substance abuse for good.
"Everyone has their own demons, and some overcome them and some never do," said fan Tya Conerly, who was among those outside the hotel, laying roses and candles at its front and back entrances Saturday night.
Grief flows at hotel where Houston died
Inside, the party went as planned, although Houston's death cast a shadow over the festivities.
"I do have a heavy heart, and I am personally devastated," Davis, who had known Houston for years, told his assembled guests. He asked for a moment of silence, and said, "We dedicate this evening to her."
Houston had performed as late as Thursday night at a pre-Grammy event in the area, a raspy rendition "Jesus Loves Me" with singer Kelly Price.
Grammy organizers hastily retooled the ceremony to pay respect to Houston, with the help of singer Jennifer Hudson.
"It's going to be something respectful," Ehrlich said. "It's not going to be a full-blown tribute. That's too early and it's too fresh at the moment."
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Meanwhile, Houston's former husband, Bobby Brown, was openly emotional at a Saturday night New Edition concert in Southaven, Mississippi, said attendee and CNN iReporter Moshiu Knox.
"Bobby was crying during his performance and at one point had to walk off stage," he said.
Knox took a video of Brown at the concert, in which he could be heard saying, "I want you all to do me a favor, just say a prayer for my daughter. Say a prayer for my mother, and if you find the time, can you say a prayer for me, because I'm going to need it."
"The crowd was emotional, and tears were flowing all over the arena," Knox said.
Houston's career: A regal rise, a tragic fall
Houston's fans were remembering her in her prime on Sunday, when she reigned as pop queen during the 1980s, selling some 170 million albums.
"Perhaps now Whitney can rest in everlasting life without the harsh judgment that she felt in this world," said CNN iReporters Kimberly and Betty Kiel from Pearland, Texas.
And in the church where Houston grew up, the New Hope Baptist Church in Newark, New Jersey, members gathered to honor her.
As a young girl, Houston grew sang solos in the choir at the church. Her mother, gospel singer Cissy Houston, served as director of sacred music at the church for 54 years and is still a member there.
Sorrow at church where Houston got her start
Whitney was born in Newark in 1963 and was soloing in the junior choir by age 11, according to the All Music Guide.
"Whitney's mother and cousins nurtured her passion for gospel music since birth," according to Houston's official website. Her cousins include singers Dee Dee Warwick and Dionne Warwick, and her godmother was Aretha Franklin.
As a teenager, Houston would accompany her mother in concert. A video posted on the Internet sharing site YouTube shows a young Houston singing the lead on the gospel song, "Have a Little Talk with Jesus," at the church.
"Whitney was a mother, a daughter, a sister, and that's the focus that we want to keep in front of everyone today, to continue to lift the family up and respect this time of grief," pastor Joe Carter said.
Asked whether he had spoken to Cissy Houston, Carter said Sunday he had, and "she needs our prayers and support."
Numerous fans took to social media to mourn Houston and note her storied career, starting with an explosion on Twitter after the news first broke. Many also posted on Facebook, recalling their favorite Houston songs. "Whitney Houston dies" was the number-one search on Google as of Sunday.
In the first hour after Houston's death was reported, the site saw more than 2.4 million tweets regarding the singer, peaking at 5:23 p.m. with 61,227 tweets, according to Topsy.com, which indexes and ranks results based on the most influential conversations on social media. That is more than 1,000 tweets per second, the site said -- "not quite as much as during the Super Bowl, but still a lot."
Nearly all of the trends on Twitter worldwide were associated with Houston's death in short order.
The outpouring continued Sunday.
"We will always love you #WhitneyHouston now in the arms (of) the angels," one Twitter user wrote.
Others quoted her lyrics: "The greatest love of all is easy to achieve. Learning to love yourself. It is the greatest love of all. #RIP #WhitneyHouston," said one tweet.