Family and friends of American pop music icon Whitney Houston have said their goodbyes to the singer at a private funeral at her childhood church in Newark, New Jersey.

Celebrities, including music greats, joined the final tribute at the New Hope Baptist Church, where Houston sang in the choir as a child. Fans showed their love with hundreds of balloons, flowers and cards piled outside the church.

The service for the 48-year-old six-time Grammy award winner and actress took place a week after she was found unresponsive in a bathtub at the Beverly Hilton hotel in California.

A gold-painted hearse transported Houston's casket to the church Saturday morning, a day after her family attended a private viewing of her body at a Newark funeral home.

Her mother, Cissy Houston, and daughter Bobbi Kristina Brown, were joined at the viewing Friday by a host of relatives, including singer Dionne Warwick, Houston's cousin. Her mentor, music executive Clive Davis, also was there.

During Saturday's service, Warwick introduced a host of soul, gospel and pop music greats from the past and present, including Alicia Keys who performed the song Prelude to a Kiss.

Houston's mentor, Clive Davis told mourners, “You wait for a voice like that for a lifetime,” while her co-star in the movie, The Bodyguard, Kevin Costner, asked mourners to “remember the sweet miracle of Whitney.”

Music legend Stevie Wonder was among the performers at Saturday's invitation-only service. Houston's ex-husband, singer Bobby Brown, put in a brief appearance at the service but close family friend, Aretha Franklin, was unable to attend because of health issues.

The private church service was broadcast live on the Internet and TV.

After the nearly four-hour-long service ended, Houston's casket was carried out as the haunting ballad that she once sang, I Will Always Love You, played over loudspeakers. She will be buried next to her father, John Russell Houston Jr., at a New Jersey cemetery.

The cause of her death is not expected to be known for several weeks, pending toxicology results.

Houston sold more than 170 million albums, singles and videos, making her one of the world's best-selling artists. But in recent years, her career faced ups and downs as she struggled with drug and alcohol abuse.