Chinese President Hu Jintao has marked the 85th anniversary of the founding of the Chinese Communist Party by calling on party members to stamp out the country's rampant corruption. The leader's warning came as his party fights to remain relevant in China's new free-market era.

With growing unrest and rising resentment over the widening gap between rich and poor, Chinese leaders in recent years have warned that corruption is threatening the survival of the Communist Party.

In a nationally televised speech Friday marking the 85th anniversary of the founding of the party, President Hu Jintao repeated the warning, saying anti-corruption efforts and creating a clean government are a "strategic mission."

"If a ruling party cannot maintain flesh and blood ties with the people, if it loses the people's support, it will lose its vitality," he said.

Anger over corruption has fueled a rising number of civil disturbances. Officials said there were at least 87,000 such incidents last year.

Many involved local officials who colluded with development companies to take peasants' land for construction projects. In many cases, peasants accuse local officials of stealing compensation money that was due to them after their land was confiscated.

Beijing has led a highly publicized campaign to expose and imprison corrupt officials, although new cases continue to crop up. The day before Mr. Hu's speech, the official Chinese news agency reported that a former high-ranking navy officer had been expelled from the national legislature for taking bribes.

In his speech Friday, Mr. Hu acknowledged that corruption is still rampant, and noted reports that party cadres are abusing power for personal gain.

However, the Chinese leader did not propose any specific reforms to fight corruption.

Analysts say it will be difficult to implement a more comprehensive system of checks and balances in a one-party system like China's, where self-scrutiny could easily be perceived as dissent.