The most prominent civil liberties activist in China, a young father who has spent much of the past 12 months under house arrest, has been jailed for three and a half years for subversion in a verdict that is likely to draw international criticism before the Olympic Games.

Hu Jia, 34, was convicted of inciting the subversion of state power. The charges against him cited comments that he made during two interviews with foreign media and five articles he wrote that appeared on the internet.

The US Embassy voiced dismay at the verdict and the EU called for Hu’s immediate release. Human rights activists said that the sentencing called into question China’s promises to the International Olympic Committee to improve its human rights record before the Games open in Beijing on August 8.

Li Fangping, one of the defence lawyers, said that the sentence was far too long. “It’s the defence position that citizens have the right to free speech,” he said. “The law on inciting subversion of state power doesn’t have a clear boundary, but the Constitution guarantees citizens’ freedom of speech.”

Hu was described as calm and poised as the sentence was read out at the Beijing No 1 People’s Intermediate Court and was prepared for the verdict. China routinely uses the nebulous charge of subversion to imprison dissidents for years.

Hu is a long-term environmental activist and advocate of rights for Aids victims, as well as a supporter of self-determination for Tibet.

Last month another dissident, Yang Chunlin, who called for human rights to take precedence over the Olympic Games, was sentenced to five years’ imprisonment for the same crime.

Hu was confined to his apartment in a complex called “Freedom City” in Beijing for more than 200 days before he was taken away by security agents on December 27. The verdict held that he had spread “malicious rumours and committed libel” in two articles on the internet, one of which was entitled One Country Doesn’t Need Two Systems.

Hu’s wife, Zeng Jinyan, 24, who gave birth four months ago to their first child and is also a prominent rights activist, wept as she left the courtroom and said that the verdict was the culmination of four years of harassment by the authorities. “He’s been put under surveillance, kidnapped. He’s been put under house arrest and now they have sentenced him to three and a half years. This is irrational and unfair.”

She, too, has in effect been living under house arrest and activists have described their baby as the world’s youngest political prisoner. She told The Times: “I can’t accept such a sentence for writing a few articles. China said it would protect human rights, but this verdict goes completely against that.”

In one article he wrote with Teng Biao, a fellow activist, that was published by Human Rights Watch, Hu told visitors coming to Beijing for the Olympics that they would see “only the tip of an iceberg” and “not the whole truth” about China.

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