BEIJING — Tensions between foreign journalists and Olympic organizers are boiling over here, with the press accusing China of flagrantly breaching its promises not to interfere in news-gathering during the games and of stonewalling basic requests for information.

At a combative daily news briefing yesterday, British, American, Australian, Hong Kong, and Japanese journalists browbeat a top Chinese Olympic official and a spokeswoman for the International Olympic Committee about the claims of ongoing interference, such as the detention and alleged assault by police of British journalists covering a Tibet-related protest near the Olympic venues on Wednesday.

“Given that China got these games largely by making promises about human rights and press freedom, and given that the Chinese government has lied through its teeth about keeping those promises, is the IOC in any way embarrassed?” a reporter for Channel 4 in Britain, Alex Thomson, asked.

“There were certainly some hopes and aspirations outlayed in 2001 as to how the games could have a positive impact on the wider social framework. And I think we have to note that there have been enormous steps forward in a number of areas. You’re here reporting on the games. The world is watching,” the spokeswoman for the international sporting body, Giselle Davies, said.

Having received no direct answer, Mr. Thomson pressed further, prompting Ms. Davies to argue, in essence, that the Chinese have made the trains run on time.

“We are very proud of the fact that these games are progressing with spectacular sport, spectacular sport venues, operationally running very smoothly. And that’s what we’re here for,” she said.

“I don’t think anybody thinks you’ve answered the question,” Mr. Thomson replied.

“The IOC’s only remit is to bring sport and the Olympic values to this country. That has been happening. And the organizers have put on an operationally sound games for the athletes. This is an event first and foremost for the athletes,” Ms. Davies said.

The spokeswoman attempted to escape the testy exchange by insisting that others would like to ask questions, but an American reporter came to Mr. Thomson’s defense. “I would have liked to hear the answer to that question, and I would have liked to have heard the answer to my question,” a freelance reporter for Fox News Radio, William Marcus, shouted.

Earlier in the session, Mr. Marcus described a series of incidents in which Chinese citizens seeking to apply to use Beijing parks designated as protest zones for the Olympics were arrested, beaten, or turned away by local officials. Asked which countries China was trying to emulate with such actions, the secretary-general of the Beijing Olympic organizing committee, Wang Wei, demurred.

“You’re in China. You’re supposed to cover the games. … I don’t know what you are saying is true or not,” Mr. Wang said. “If you have questions like that, the protesters, things like that, you should go to the authorities of public security.”

A reporter from Hong Kong, Peter Simpson of the South China Morning Post, told Mr. Wang he might not have received “such a ferocious roasting” if he provided some figures on how many applications have been made to demonstrate in the seemingly unused protest zones. He said he would relay such numbers when he got them.

When he helped lead Beijing’s Olympic bid in 2001, Mr. Wang vowed that the Olympics would bring greater respect for human rights in China, and he pledged unfettered access for journalists.

“We are confident that, with the games coming to China, we are going to not only promote the economy but also enhance all social sectors, including education, medical care, and human rights,” Mr. Wang told reporters one day before the Olympics were awarded to Beijing, according to Agence France-Presse. “Certainly, we will give the media complete freedom to report on anything when they come to China.”

Yesterday, Mr. Wang said he was not promising specific changes in China, but he was pledging to change perceptions foreigners hold about the country. “I did not say that China will promise to do whatever with the games to China. I did not say that. But I say the games will open the horizon about China. People will see better for themselves what China’s like,” he said. “I think a few, a very few people come here to pick, to be critical, to dig in to the small details, to find fault with that — that does not mean we are not fulfilling our promise.”

When Mr. Thomson attempted to pursue the issue further, Mr. Wang bristled. “This is not a debate. You have your turn. I have mine. Okay? Thank you,” the official said.

In the latest incidents, a British television reporter, John Ray of ITN, was detained for about half an hour, and a British photographer, Dan Chung of the Guardian, reported being manhandled and having his camera broken by police while covering a Tibet-related protest by foreigners at a minority culture theme park near the main Olympic sites.

“Media should be allowed to do their job, and we disapprove of their work being hindered when they do not appear to be breaching the rules. I can’t be more clear than that,” Ms. Davies said yesterday.

A journalist from a Japanese news outlet also complained that a question about the impact of the new military conflict on relations between athletes from Georgia and Russia was rejected by an official moderator during a news conference with judo champions Wednesday night.

Mr. Wang defended censoring the question as a way to respect the Olympic Charter’s ban on political and religious proselytizing at the games. “I think I understand why the M.C. would not encourage questions like Russia-Georgia to happen, because if it starts a debate, it will not end up very happily. It will upset the Olympic spirit here,” Mr. Wang said. The IOC did not respond to requests for comment on the episode.