BEIJING — What do Jiangsu Province, the minor pop idol Jiang Yirong and Huadong Hospital in Shanghai have in common? Over the past day, these and scores of other words and expressions have been blocked on much of the Chinese Internet, a result of the government’s unrelenting attempt to quash widespread rumors that the former Chinese leader Jiang Zemin is dead or dying.

Not surprisingly, the stepped-up effort to silence speculation about the well being of Mr. Jiang, 84, who officially retired as party chief in 2002 and as president in 2003, has generated even more rumors since last Friday after he failed to attend the 90th anniversary gala commemorating the birth of the Chinese Communist Party.

On Thursday morning, the official Xinhua News Agency issued an English-language response to the reports that Mr. Jiang had died, saying they were “pure rumor” and quoting what it said were “authoritative sources.” Later in the day, during a regularly scheduled news conference, a Foreign Ministry spokesman declined to answer any questions about Mr. Jiang’s health, referring journalists to the Xinhua statement. That exchange, however, was curiously omitted from a transcript of the news conference posted on the ministry’s website.

While China’s ruling party has not in recent years suppressed news about the death of an important leader, officials rarely, if ever, discuss the health of current or former leaders, and they ban news coverage of those subjects.