Special Olympics competitors were greeted by a logistical nightmare upon their arrival in Southern California, with many forced to sleep on a gymnasium floor before they were shuttled to their host cities Wednesday.

At least 1,500 athletes and coaches spent the night at Loyola Marymount University in Los Angeles after flights and buses arrived late Tuesday, Special Olympics spokesman Rich Perelman said.

Athletes from Norway, Mexico, Venezuela, Kenya, the Cayman Islands and other countries were on their way to their host cities by midday Wednesday, just in time to clear the way thousands more that were scheduled to arrive Wednesday afternoon.

"It really wasn't bad," Collins Marigiri, the Kenyan team's swim coach, said as he and his athletes boarded a bus for their host city of Bakersfield. He added with a smile that it was his and his team's first trip to the United States, so even getting stuck overnight in a college gymnasium was a new and interesting experience for them.

"The athletes didn't have any problems," Marigiri said. "They had food. They had water. They had a place to sleep. There were no medical issues."

The Red Cross provided blankets and water.

The university near one of the busiest airports in the world – Los Angeles International – is serving as a staging area from which approximately 6,500 athletes and thousands more coaches and delegates are being routed to host cities, from San Diego to San Luis Obispo. They will be housed there until opening ceremonies Sunday.

Problems started when some international flights were delayed and buses assigned to meet them began stacking up. Minor construction near the airport caused traffic tie-ups as well.

"Flights arrived late and buses got backed up. The process just got so elongated that the decision was made to keep them here until morning," Perelman said.

Some athletes had to spend a couple of hours at the airport waiting for their connection to the welcome center. However, airport police Officer Rob Pedregon said the process was orderly and uneventful.

While some of those stranded were tired after their long trips, the majority made the most of the circumstances, Perelman said, playing board games and making friends with fellow athletes from other countries. Some took part in sing-alongs and at one point formed a conga line.

"Everyone was very happy when breakfast arrived at 6:30 a.m.," Perelman said. "That was the highlight."

Competitors from more than 160 countries are arriving in Los Angeles this week to take part in 25 sports at venues across the city.

Athletes ages 8 to 71 will compete in soccer, basketball, volleyball, tennis, track, roller skating and other sports over nine days.

First lady Michelle Obama will open the event Saturday at the Los Angeles Memorial Coliseum, site of the 1932 and 1984 Summer Olympics.

ESPN is broadcasting the opening ceremony live.

The Associated Press contributed to this report.