Mr Guo, who was held by the authorities on several occasions over the past two years, had also published criticisms of the Chinese government on the internet. He highlighted its initial refusal to accept foreign help after a huge earthquake in Sichuan province in May. Mr Guo also publicized the plight of peasants who have been dispossessed in land conflicts and unemployed factory workers.

The sentence follows an extremely tense 18-month period for dissidents in China which has seen a number of crackdowns by the authorities.

As well as the heavy restrictions on activists before and during last year's Olympics, an event which many observers had hoped would lead to an improvement in human rights in China, there have been also been crackdowns around a number of important anniversaries this year. These included the 20th anniversary of the Tiananmen Square protests in June, the 50th anniversary of the Dalai Lama's flight from Tibet in March and this month's celebrations of the 60th anniversary of the founding of the People's Republic of China.