LOS ANGELES (CBSLA.com) — Special Olympics athletes from all over the world arrived at Loyola Marymount University Tuesday to officially sign in for the World Games.

About 6,500 athletes with intellectual disabilities and 2,000 coaches – representing 165 countries – will be taking part in the nine-day event at venues across the Los Angeles area, beginning with the opening ceremony scheduled for Saturday at Los Angeles Memorial Coliseum.

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As athletes and coaches began arriving at Los Angeles International Airport Tuesday, they were loaded into buses and taken to Loyola Marymount University in Westchester, where they received the red-carpet treatment, greeted by cheerleaders, photographers and other supporters.

Once checked in, the athletes were taken to their respective host cities, which they will call home throughout the nine-day games.

About 30,000 volunteers are expected to lend their services during the games, which will be attended by an estimated 500,000 people.

The games will feature 25 Olympic-style sports in various venues through Aug. 2.

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Saturday’s opening ceremony will feature first lady Michelle Obama, along with performances by Stevie Wonder, Avril Lavigne, Nicole Scherzinger, O.A.R., Cody Simpson (featuring Special Olympics athlete Breanna Bogucki and YouTube sensation Madison Tevlin), J Balvin & Becky G, and Reach Up LA theme song creator Siedah Garrett.

Also scheduled to take part in the opening festivities are Jimmy Kimmel, Eva Longoria, Michael Phelps, Yao Ming, Greg Louganis, Stephanie McMahon and Lauren Potter, among others.

Competition events are free and open to the public. Tickets for the opening ceremony are available for purchase at LA2015.org via Ticketmaster.

The first lady serves as an honorary co-chair of the World Games along with President Barack Obama.

To buy discounted tickets to the Opening Ceremony, enter code “WGFANS” at http://bitly.com/LA2015discount.

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