This weekend more than 24,000 members of an American Buddhist sect called Nichiren Shoshu Soka Gakkai of America (NSA) will converge on Washington for an extravaganza called "Aloha, We Love America." Tourism officials say it will be one of the biggest such gatherings ever held here.

"It is extremely unusual that this many people come in one group to D.C.," said Austin Kenny, executive vice president of the Washington Convention and Visitors Association. He said the average convention here draws 900 to 1,000 people.

If 25,000 persons attend, as NSA leaders expect, the gathering will inject about $6 million into the area's economy in just two days, according to Kenny, who projects that the participants will spend an average of $200 to $250 each.

NSA is an offshoot of the Japanese branch of the Soka Gakkai, a Buddhist organization with 20 million members in Japan and 250,000 in America. NSA is dedicated to world peace, leaders of this weekend's event say.

"We believe that the cause of peace can be developed through cultural exchange, developing bonds of mutual understanding and respect among all people," said George Williams, the organization's leader and an Asian who adopted his western name when he became an American citizen.

To pay for the celebration, each attending NSA member will contribute $20, and much of the preparation has been done by volunteers, organizers report.

"Aloha, We Love America" will be a fast and furious 48 hours if all goes as NSA expects. All scheduled events will take place on the Mall except a Sunday morning parade along Constitution Avenue in which 10,000 NSA members will march, each displaying a three-by-five-foot American flag.

A music and dance show beginning at 7 p.m. Saturday will feature a 150-member orchestra made up of musicians from across the country, singer Tina Turner and jazz artist Herbie Hancock, both NSA members. Other acts will include performances by Broadway dancers, a flamenco dance team, and a troupe of 400 hula dancers from Hawaii, touted as the largest ever to perform on the U.S. mainland.

Why are Buddhists, viewed widely as observing a strict religion, holding a festival of such grandeur? Liz Hughs, a press spokeswoman for the group, said, "Our sect of Buddhism wants to celebrate the grandeur of our country and the grandeur of mankind.

"We do not tell people to eradicate their desires. We believe desires motivate people to change, and we hope our celebration will inspire people to realize this," Hughs added.

Gary Treon, chief of special events for the U.S. Park Police, said he expects the events to run smoothly. He said he checked with police in other major cities where NSA has held celebrations and found that the organization had no record of trouble at those events.