China has sent human rights lawyer Gao Zhisheng back to jail, state news agency Xinhua reported on Friday, ending his probation in what was the first official account of his whereabouts in the last year.

Gao, however, appears never to have escaped secretive confinement in the first place.

A combative rights advocate who tackled many causes anathema to the ruling Communist Party, Gao was sentenced to three years' jail in 2006 for inciting subversion of state power, a charge often used to punish critics of one-party rule.

Gao was given five years' probation, formally sparing him from serving the prison sentence. But his family was under constant surveillance and Gao was detained on and off over that time.

He was taken from a relative's home in Shaanxi province in northern China in February 2009 -- his family claims by security officers -- and had been missing since early last year, when he resurfaced briefly and made sporadic contact with friends and foreign reporters in April 2010.

Xinhua, in a brief story that appeared only in English, said a Beijing court withdrew probation on Gao and sent him back to jail.

He had seriously violated probation rules a number of times, which led to the court decision to withdraw the probation, Xinhua cited a court statement as saying. It did not give details of Gao's alleged violations.

He would serve his term in prison, referring to the three-year sentence, the report added.

Xinhua said that the court had put him back in jail.

Gao's older brother, Gao Zhiyi, told Reuters he had not been told about the court's decision, despite his repeated appeals to police for any word of his brother's whereabouts.

Gao's wife Geng He, who fled to California with the couple's children, told Reuters she wasn't sure whether to be gratified or despondent over the news of her husband, whom she has not seen since January 2009.

We kept on asking: 'Where is he? Where is he?' The government has not given us a single word, until this day, that we've got the news about him. Now we know that he still exists. Before this came out, we thought he was dead, Geng said, speaking in tears.

I plead with the international community and the Western media to keep their focus on the Gao Zhisheng case. This persecution cannot continue. We will hire a lawyer to represent him, Geng said.

BEIJING ASKED TO CLARIFY GAO'S LOCATION

In Washington, the U.S. State Department said it was disappointed that Gao had been returned to jail and called on Beijing to immediately release him and clarify his whereabouts.

The forced disappearance of Gao is a serious human rights concern and demonstrates that Chin is not living up to its commitments under the Universal Declaration of Human Rights, State Department spokeswoman Victoria Nuland said.

We again express our deep concern over the continued use of extralegal measures against Gao and other human rights activists, and urge China to uphold its internationally recognized obligations.

Nicholas Bequelin, a researcher on China for New York-based Human Rights Watch, said the news did not allay fears about the lawyer's well-being.

This seems to be further proof of the politically motivated persecution against him, he said. It is a continuation of his detention and deprivation of freedom. It's essentially preventing him from talking about what happened.

Catherine Baber, Amnesty International's deputy director for the Asia-Pacific, said the news about Gao was truly shocking.

The international community must not let up on the condemnation of the travesty of justice, she told Reuters.

Mo Shaoping, who previously served as Gao's attorney, said Chinese courts had no obligation to hold a hearing or even notify the accused that probation might be rescinded.

Chinese procedures on this point are a blank, Mo said by telephone. The public security authorities can apply to the court, and then the court simply has to give its written decision, and there's no prior notification or hearing.

The United Nations working group on arbitrary detention said in March that Gao was being detained in violation of international law.

Starting in February, China mounted a crackdown on potential political challengers to the ruling Communist Party, fearing that anti-authoritarian uprisings in Arab countries could inspire protests against one-party rule.

Many rights lawyers were detained, and most who have since been released have refrained from speaking out or renewing high-profile advocacy, fearing fresh bouts of detention.

CNN said on Friday that British actor Christian Bale was roughed up by Chinese security guards as he attempted to visit a blind legal activist whose detention has sparked a domestic and international outcry.

(Writing by Ben Blanchard; additional reporting by Andrew Quinn in Washington; Editing by Nick Macfie)