BEIJING – Even as China’s president ordered an investigation into a New Year’s Eve stampede in Shanghai that killed 36 people, the nation’s censors and police were hard at work – restricting independent reporting of the incident, curtailing interviews with relatives of the victims and intimidating critics.

Shanghai police have admitted they failed to deploy enough officers to control a large crowd that had collected on the city’s waterfront Wednesday night, after underestimating the number of people who would turn up.

Nevertheless, with some officers fearing they could lose their jobs, the force did not take kindly to criticism. Dozens of people who posted critical comments online were subsequently interrogated by police, “as a warning to those unfriendly Internet users,” one police officer told the South China Morning Post, asking not to be identified.

The paper said several interviews with relatives of victims were interrupted by people who described themselves as “volunteers” at a Shanghai hospital, and who argued the interviews were “improper.”

Central government authorities also issued strict guidelines to domestic media organizations demanding they “strictly use authoritative copy from central and Shanghai major news units,” and avoid using material from commercial Web sites, according to the China Digital Times Web site, which tracks censorship instructions.

"Using information from Weibo, WeChat, other social media, or foreign media is strictly prohibited,” the instructions said. “The use of inaccurate or incomplete information published by netizens who were at the scene is strictly prohibited. Publication of excessively tragic and bloody images is strictly prohibited.”

In an implicit acknowledgement of how serious an embarrassment the incident has become, censors also demanded media “delete malicious information, remove opportunities to attack the Party and the government, and information attacking the social system.”

Nevertheless, state-run media acknowledged that the local government could not escape responsibility for the incident on the city’s famous waterfront, known as the Bund.

"It was a lack of vigilance from the government, a sloppiness," the Xinhua news agency wrote in a commentary. "The disaster, which happened in China's financial hub of Shanghai, served as a wake-up call that the world's second-largest economy is still a developing country which has fragile social management."

President Xi Jinping last week told Shanghai officials to provide an explanation of what went wrong, and said that local officials around the country should ensure that no repeat of the incident occurs elsewhere during next month’s Lunar New Year festival.

But some Netizens asked whether a credible investigation was possible when censors were so determined to suppress information about the incident.

"No resignation, no apology, no responsibility, no accountability, only block it out,” said one user of the Weibo social media service.

"It happened, we have to face it, solve it and avoid it happening again,” wrote another. “What's the meaning of controlling public opinion? Where's the confidence? It will only backfire, and produce the opposite result.”

Liu Liu contributed to this report.