The chat aboard China's G21 bullet train began with talk about the recent crash of two high-speed trains that killed at least 40 people in eastern China, but soon the bureaucrat in a pink polo shirt was discussing the Chinese government.

"I think the government emphasizes visible things: When they build a new city, the city looks amazing, but when there's a storm, there are problems with flooding," said the man, whose surname is Wang but whose first name is being withheld to avoid getting him in trouble. "The city is visible, but the sewage system is not."

Was he nervous, then, about being on the bullet train from Beijing to Shanghai? Mr. Wang, who works at a government finance department, gave it a moment's thought and answered that the "accident horrified people, but they don't have a better choice than the train."

More than anything, the aftermath of the high-speed train wreck last month in Zhejiang province has come to underline the fact that for all of China's enormous economic growth, the nation is still overseen by an opaque, authoritarian regime frequently plagued by corruption. It's a system that relies in large part on the promise of material progress for its people, with the threat of heavy-handed tactics for those who step out of line.

During the past nine days, that approach has seemed especially off-balance.

In trying to explain, or not explain, the events that caused one train to rear-end another on July 23, officials ordered the media to censor reports on the accident, made announcements that strained credulity and then blamed a confusing jumble of factors including lightning, badly designed equipment and poorly trained workers.

Interviews with passengers on the trip between Beijing and Shanghai over the weekend suggested that in addition to worries about rail safety, the incident has for some reinforced a sense of unease with the pace of the nation's development.

No one spoke about a seismic shift that would threaten the government's hold on power, but most obviously had spent time thinking about the implications of the wreck.

"I think it's an issue of national credibility," said one passenger, who asked that only his last name, Lin, be used. "Other countries took 100 or 200 years to develop to this level. We took 10 or 20 years, so there are bound to be problems."

Like many others on the train, Mr. Lin, in a pressed aqua polo shirt and khaki slacks, had the look of the relatively affluent, the sort of man who's benefited from China's financial rise.

At the end of the day, said Lin, a real estate investor, "I have to believe the government because I cannot walk to where I'm going."

Sensitive subject

The subject of train infrastructure was a sensitive one even before the accident. While Beijing's plans to lay down 10,000 miles of track for high-speed trains by 2020 has wowed Western observers, the initiative is viewed with a mix of emotions in China.

The high ticket prices for high-speed trips are a sore point for many, as are suspicions that corruption wracks the project.

In February, Railways Minister Liu Zhijun was dismissed from his post amid allegations that he'd received kickbacks of at least $122 million.

Liu's replacement confirmed to state media in April that ticket fares would be lowered and that the trains would run at slower, and presumably more manageable, speeds. The second measure brought worries that corners may have been cut during construction.

Skepticism about the rail system shot to the fore in the wake of the July 23 accident.

Media blackout

The government almost immediately ordered China's domestic news services to avoid investigating the causes of the disaster and to emphasize the government's understanding of the tragedy in their coverage.

But the guidelines were ignored by Internet users who swarmed a Twitter-like Chinese site named Weibo with a series of damning photographs. The images included pictures of sections of a train car being buried while bodies were widely thought to be still in the wreckage.

As one passenger on the Beijing-Shanghai train put it, "I don't watch official Chinese media. I get my news on Weibo and other Internet sites."

Li Changxi, a 20-something construction equipment salesman, paused while typing on his laptop to explain that between the rumors on Weibo and official propaganda, "I need to judge for myself what is true."

Two days after the crash, a Chinese state TV anchor, Qiu Qiming, made a widely quoted on-air appeal: "Can the roads we travel on in our cities not collapse suddenly? Can we not travel in safe trains? And if and when a major accident happens, can we not be in a hurry to bury the first carriage of the train?"

Mr. Qiu concluded: "We want to say: 'China, please slow down. Don't go too fast, and don't leave the people's soul behind.' "

On Friday, the central government issued a directive that again pushed to curtail critical reporting about the railway system, and this time was more successful. Most publications complied, sticking to state news-wire coverage.

But not everyone. The Beijing-based Economic Observer ran a special section and a front-page editorial, in the form of a letter to a 2-year-old girl who was found after the government had declared that there were no more survivors. The newspaper is a weekly, and there were reports that it went to print before the government's instructions came through. Nonetheless, it was still available at public newsstands Monday morning.

"On behalf of you lying there on that sickbed and those lives buried in the ground, people are refusing to give up on finding the truth," the editorial said.

Inside the newspaper, the section on the crash began with the image of a bloodstained ticket from D301, one of the trains in the wreck.

Also on Monday, an unsigned post was spotted on a Weibo account verified as belonging to China Central Television, the state broadcaster. It said that Zhang Shuguang, a former deputy chief engineer at the Ministry of Railways who was removed from his job amid corruption allegations, is accused of having deposits abroad of $2.8 billion.

The item, which has appeared in various forms on other Chinese websites, didn't include any sourcing or proof for the seemingly outrageous figure. Still, there it was, publicly displayed on a CCTV account. And then, without explanation, it disappeared.