Witnesses said scuffles broke out at one ticket site as officials opened additional sales windows at the last minute, causing some fans to stampede ahead of others in a bid to buy some of the 250,000 tickets that went on sale in different parts of the host city.
"It was so unfair," said Ji Liqiang, who waited for 28 hours with Wang Zhenqiang, a fellow businessman from eastern Shandong province, for a chance to buy tickets to the diving competition.
"Those who came late but were able to push forward got the tickets," he said.
The two lost their place in line in the scramble and ended up with tickets to the synchronized swimming instead of diving -- where China is a gold-medal favorite.
"It was very dangerous. I was afraid," Wang said. "People got hurt around me. They fell and injured their knees and elbows. A barricade was bent out of shape by the crowd."
Zhang Xiaojing, 17, who came from Hebei province with her cousin and three friends, said the line was fairly orderly when she arrived Thursday afternoon. But during Friday's rush, only three of her friends were able to elbow their way close enough to be in a position to buy tickets.
"If I'm going to be disappointed, I'm going to be disappointed. But I'm so tired. I didn't sleep last night," she said.
The official Xinhua News Agency said 30,000 people lined up for tickets, but muggy weather with temperatures above 93 degrees Fahrenheit coupled with the long wait made people impatient. Police immediately took actions to maintain order, including limiting access to some areas, it said.
Some journalists were escorted away after going into the off-limit areas, Xinhua said. Hong Kong television showed several journalists pushing back and forth with police.
Footage from Hong Kong Cable TV showed a policeman putting his arm around the neck of a Hong Kong Cable TV reporter and pulling him to the ground. The reporter said he was assaulted after his crew refused to leave a media zone, Cable TV reported. They were seen surrounded by dozens of police.
A spokeswoman for Hong Kong Cable TV said it was "unacceptable" for Chinese authorities to treat the media that way.
"We hope the authorities will live up to their earlier promise to allow full freedom of the press during the Olympic Games," said Shum Siu-wah.
Despite the problems, an Olympic official said the start of the sale went well.
"There were so many people who wanted tickets so we decided to open more ticket windows. ... In general, so far the ticket sale has gone smoothly," said Sun Weide, spokesman for Beijing's Olympic organizing committee.
At Wukesong in the western part of Beijing, tens of thousands of people were lined up to buy tickets for the popular basketball competition. About 20,000 basketball tickets were expected to go on sale.
In addition to the tickets for Olympic events in Beijing, another 570,000 tickets are on sale for football matches in co-host cities: Tianjin, Shanghai, Shenyang and Qinhuangdao.
All told, 6.8 million Olympic tickets have been available for domestic and foreign sales. The Olympics start Aug. 8.
Though previous Olympic Games have had problems filling seats for less popular events, venues in Beijing are expected to be filled with enthusiastic fans. Some tickets were given away to school groups and government work units in an effort to present packed stadiums to television viewers around the world.
In November, organizers were embarrassed when the computer system crashed, forcing organizers to sack the Olympic ticketing chief and revert to a lottery system to sell tickets.
Organizers have said they are taking precautions against fake tickets and black market scalping, both of which are common in China. Buyers on Friday were limited to two tickets per person to discourage scalpers.
Xinhua said Thursday that Beijing police have detained 60 suspects for scalping Olympic tickets in the past two months, citing a police spokesman. Those found selling tickets on the black market can face 10 to 15 days in detention, Xinhua said.
Still, Olympic tickets can easily be found online, though few sellers openly advertise the resale price. In sports that are unpopular in China, like baseball, 50 yuan ($7.30) tickets were offered at 1000 yuan ($150). Other tickets were being resold for 100 times the face value, Xinhua said.
