Whitney Houston's friends and family joined music and film celebrities and hundreds of mourners in a packed New Jersey church for the late pop icon's funeral, where she was remembered as a "sweet miracle" and one of the greatest singers in the world.

The crowd of mourners packed the aisles of New Hope Baptist Church in Newark, where Houston, who died a week ago, sang as a child with the congregation's choir.

In his remarks, Kevin Costner, Houston's co-star in the Hollywood blockbuster film The Bodyguard, said Houston was "as beautiful as a woman could be."

"Whitney returns home today to the place where it all began, and I urge us… to dry our tears, suspend our sorrow and perhaps our anger, just long enough, just long enough to remember the sweet miracle of Whitney," Costner said.

Friends also remembered the pop icon's voice, sense of humour, kindness and deep faith.

Director-producer Tyler Perry recalled Houston's strength to the crowd of hundreds that filled the church.

"There was a grace that kept on carrying her through," Perry said at the church's pulpit. "The same grace that led her to the top of the charts, sold off all the albums, and done all these amazing things."

Gospel singer Bebe Winans, a close friend of Houston, recalled how Houston, at the height of her career, offered to sing backup for him on his first major headline tour with his sister, Cece Winans.

To Houston, he dedicated a song, originally written for his brother who died, called "I Really Miss You."

"I miss your wit, miss your charm," he sang. "Just want to hold you in my arms.. I miss your voice, when you would call. I miss your smile, most of all."

Alicia Keys also played the piano and sang a song dedicated to the late pop star.

"Whitney is an angel … And we're never going to forget you," she sang.

A gospel choir, members dressed in white and gold, opened the funeral with song, and churchgoers were swaying and clapping along. Some stood in the aisles in the full church.

The mayor of Newark, N.J., Cory Booker, addressed the crowd gathered in the church, calling Houston "one of our angels."

"We are here to mourn our loss, but to celebrate her life," he said.

Singers Chaka Khan, Brandy, Roberta Flack, Jordin Sparks, Jennifer Hudson and Rev. Jesse Jackson were among those in the pews. Brandy comforted her brother, Ray-J, a singer who spent time with Houston during her final days.

A couple of hours before Saturday's funeral, scheduled to begin at 12 p.m. ET, blockades around the church parted to allow in the golden hearse carrying Houston's body in a silver casket, draped with white roses and purple lilies.

A program featuring a picture of Houston looking skyward read "Celebrating the life of Whitney Elizabeth Houston, a child of God." Pictures of Houston as a baby, with her mother, gospel singer Cissy Houston and daughter, Bobbi Kristina filled the program. Her mother wrote a letter thanking her for being a "wonderful daughter," signing the letter, "mommie."

Houston, a prominent figure in the gospel and soul music community, was the daughter of soul and gospel singer Cissy Houston and a cousin of singer Dionne Warwick.

Stevie Wonder will reportedly sing at the service, while other big names expected to attend include Beyonce and Jay-Z, Elton John, Alicia Keys and David Bowie.

Aretha Franklin was expected to attend, and sing at the funeral, but a person close to the Houston family said Franklin is sick and would not be there.

Houston's longtime music producer and mentor, Clive Davis, and actor Kevin Costner, her co-star in the film The Bodyguard, are expected to speak at the funeral. Her ex-husband Bobby Brown has also reportedly been invited by the family.

Newark police announced that six square blocks around the New Hope Baptist Church would be cordoned off Saturday and that fans would not be allowed in.

Newark police director Samuel DeMaio advised fans to stay home to watch the funeral, which is being broadcast on TV and streamed live online. He also said there would be no procession from Newark's Whigham Funeral Home, where Houston's body is resting, to the church.

Despite DeMaio's message, however, fans are expected to gather outside the police cordon to pay their respects.

Groups of mourners had already made their way to the church Friday morning, erecting a makeshift memorial of balloons, photos, homemade signs and flowers on the sidewalk outside the building.

Devotees have also left tokens of remembrance to the singer outside the funeral home and a school that bears her name. Fans have appealed for a public memorial where they can unite to grieve.

On Saturday morning, a few fans gathered hours before the service as close as they could get to the church, some from as far away as Washington, D.C., and Miami.

Others were more entrepreneurial, setting up card tables to sell silk-screened T-shirts with Houston's image and her CDs. But only the invited would get close to the church; streets were closed to the public for blocks in every direction.

One fan said he was there "just to be among the rest of the fans."

"Just to celebrate her life, not just her death," said Bobby Brooks of Washington. "Just to sing and dance with the people that love her."

Gospel singer and Pastor Marvin Winans — of the prominent, Grammy-winning family of gospel singers — is expected to deliver the eulogy. Winans presided over Houston's wedding to fellow singer Brown in 1992 and his family has long been friends with the Houston clan.

The 48-year-old singer died last Saturday on the eve of the 2012 Grammy Awards. She was discovered unconscious in a bathtub at the Beverly Hills Hilton Hotel. Her death came just hours before she was slated to perform at a pre-Grammy Awards party.

Authorities said an autopsy found no indications of foul play or signs of trauma, but that it could take weeks before the coroner's office completes toxicology tests and determines the cause of death.

The singer's death cast a pall over the Grammy Awards ceremony, triggered a wave of tributes online and impromptu memorials in public spaces around the world.

Addiction woes

Houston's death has also generated some controversy.

New Jersey Gov. Chris Christie was criticized for ordering that flags be flown at half-mast during Houston's funeral. Christie defended his decision, saying that Houston's problems with substance abuse should not detract from her accomplishments.

In Los Angeles, KFI AM 640 suspended John Kobylt and Ken Chiampou, the outspoken hosts of its talk radio program The John and Ken Show, after they called Houston a derogatory name and said on air that the singer was "cracked out for 20 years." The pair subsequently issued an apology to Houston's family and their listeners in a statement.

Rev. Jesse Jackson, a friend of the Houston family who will be at the funeral Saturday, spoke of her addiction problems in an interview with CBC-TV's Connect with Mark Kelley Friday night.

"By her own admissions she had had a couple of relapses. She was fighting this demon," Jackson said.

"At the end of the day Whitney is a winner. But her pain should teach us lessons, because I hope those people who need help will get help and will not feel that they have to conceal their pain until it's too late."

Houston's final resting place will be next to her father, John Russell Houston Jr., at the Fairview Cemetery in Westfield, N.J., a source close to the family told The Associated Press.