Jane Macartney, The Times China bureau chief (left), explains why the sacking for corruption of Chen Liangyu, the top Communist official in Shanghai, has plenty of political overtones:

Who is Chen Liangyu?

Chen is a very experienced politician who had made his entire career in Shanghai and was, until today, a member of the Politburo and so one of the most powerful men in China. He was in charge of China's most exciting and cosmopolitan city -- the face that China wants to present to the world.

He had held onto his position as Party Secretary in Shanghai in the face of some pressure from Hu Jintao, the Chinese President, not just because of the rising corruption scandal, but because he is seen very much as an ally and protege of Jiang Zemin, Hu's predecessor. He owed his position and his profile to Zemin and for that reason was seen as a rival to Hu's own supporters in the party leadership.

Was this a corruption scandal or a political purge?

It's both. It's pretty easy to go to any Chinese town or province these days and discover corruption going on between local businessmen and party officials. And there were plenty of people in the party leadership in Beijing who would have been pleased to find a serious scandal going on in Shanghai.

The corruption involved the misuse of the city's social security fund - its pensions, in other words - and the giving of a loan to a road building company. As far as we can work out, the road builders blew the whistle on the scandal to the Communist Party's "Central Commission for Discipline Inspection" just as they were preparing to pay back the loan.

What is the nature of the rivalry between Hu Jintao and Jiang Zemin?

The two men have very different personalities and leadership styles but, in a sense, Hu is doing exactly what Ziang did once he was safely in power: that is, clearing out the leadership of the party for potential rivals.

There is a clique of senior officials, including Chen, who came to prominence under Ziang. Ziang is seen very much in China as the man who wanted to make people rich - and under his rule, the rich got richer.

Hu, by contrast, has been keen to portray himself as the man of the people, helping those who have been left behind by reform. Exposing the leader of Shanghai, China's richest city, as corrupt plays into that very well.

How will people see this in Shanghai?

The first reaction of many people in Shanghai will be anger that their pensions were being fiddled with. There is a looming pension crisis in China - an ageing population and the recent economic upheavals have made people very anxious. The reason many people in China are trying to save so much of their wages is that they fear they have no protection from the state.

And many people will be pleased that the corruption has been exposed. Corruption is an enormously emotive subject in China. I can't over-estimate how enraged people feel to see party officials misusing their position to benefit themselves and their families.

But there is a loss of face to for Shanghai. People are proud of their city and sensitive to criticism from Beijing and the rest of the country, who see it as a centre for sly businessmen and profiteering.

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