Fox News: Los Angeles city officials are preparing for massive crowds downtown during Tuesday's public memorial for Michael Jackson at Staples Center.

Assistant Police Chief Earl Paysinger says anywhere from a quarter-million to 700,000 people may try to reach the arena, even though a wide area around Staples Center will be sealed off to those without tickets.

City Councilwoman Jan Perry strongly urged people to stay home and watch the memorial on TV. The ceremony will not be shown on Staples' giant outdoor TV screen and there will be no funeral procession through the city.

But public safety officials appeared to assume their requests to stay home would have little effect. Since Jackson's death, fans have flocked to Jackson sites from Los Angeles to his Neverland Ranch in rural Santa Barbara County.

Tim Leiweke, CEO of AEG Live, announced Friday that 17,500 tickets will be made available to fans via a Web lottery to attend the service. Eleven-thousand tickets will be issued for the Staples Center and an additional 6,500 will offer seats to watch a live simulcast at the nearby Nokia Theater.

Fans interested in attending the memorial service can apply for the lottery at the Staples Center Web site. Registration began at 10 a.m. PT and will continue until 6 p.m. PT on Saturday. A computer program will randomly select 8,750 names to receive two tickets for one venue or the other, he said. Those selected to receive tickets will be notified between 11 a.m. and 8 p.m. Sunday, and will be given a code to use at the Ticketmaster.com Web site, which will give them further instructions on where to go Monday morning to get the tickets and wristbands enabling them to enter the venues, Leiweke said.

The area around Staples and Nokia will be blocked off by police, and there will be no outside broadcast in or around Staples Center. But the service is being offered free to TV networks, so fans who do not get tickets were encouraged to watch the service from the comfort of their own homes, said Perry, who is acting mayor while Antonio Villaraigosa is on vacation in South Africa. Perry said police have a contingency budget for expenses like the memorial.

"It's calculated in the budget," Perry told Reuters. "We don't know what the estimated cost -- what they may expend -- is yet."

It also was unclear how much AEG may be chipping in. AEG is part of a group of companies including AEG Live, the concert promoter that was backing Jackson's planned London shows.

Perry said other city services such as sanitation and transportation were not covered by the police budget. She said she would seek help from other agencies involved to help pay.

Like other U.S. cities, Los Angeles is strapped for cash in the global recession and similar questions about public tax revenues being paid for such an elaborate ceremony surfaced last month when a $2 million celebration was given for the champion Los Angeles Lakers professional basketball team. That event was eventually funded through private donations. Organizers also said there will be no funeral procession as had been rumored.

Organizers had no details on the family's plans for a private service for the pop star, nor did they offer details about the public service itself.

Jackson's brother Jermaine told CNN's Larry King that there will be a private ceremony for family and some special guests before the public memorial. Access Hollywood confirmed Friday that the private funeral will be held at Forest Lawn Memorial Park in Los Angeles.

Meanwhile, the future of Michael Jackson's children was thrown into question Thursday when his ex-wife emerged and won a delay in a custody hearing while she decides whether she wants to raise her two offspring.

It was the first legal move from Deborah Rowe since the entertainer's death. Jackson's will asks for his 79-year-old mother, Katherine, to get permanent custody of his three.

Rowe, who met Jackson as a receptionist in the office of his dermatologist, has characterized their relationship as strictly for the purpose of giving birth to Jackson's children. She is the mother of his two oldest children and received $8.5 million in their divorce, according to court records. His youngest child, 7-year-old Prince Michael II, was conceived with an unidentified surrogate.

Rowe has spent little time with her son Michael Joseph Jr., known as Prince Michael, 12; and daughter Paris Michael Katherine, 11. But Rowe also has opposed the idea of Katherine Jackson getting custody of her children when it came up in the past.

Rowe's attorney, Eric M. George, said his client had not decided whether to seek custody.

A guardianship hearing was set for July 13 at the request of attorneys for Rowe and for Katherine Jackson, who has temporary guardianship of her son's children.

In other developments:

A 30-second snippet of Jackson rehearsing for a series of comeback concerts in London two days before his death was released Thursday. The rehearsal footage, shot in high definition, includes Jackson performing his hits "Thriller" and "Beat It." His voice is strong and he appears in perfect health. Other footage shows production meetings and auditions.

A court hearing was scheduled for Monday to deal with who will take temporary control of Jackson's estate. He left all his assets to the Michael Jackson Family Trust. A person familiar with the details of the trust said it would be shared between his mother, who gets 40 percent, his three children, who together get 40 percent, and charities for children, which would receive 20 percent. The charities will be determined later by the trust. The person was not authorized to speak publicly and spoke on condition of anonymity.

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