BEIJING (AP) _ The Chinese government claimed Thursday that an American human rights activist charged with spying has confessed to using false identities and documents to film news reports about Chinese prisons.

The government unleashed its broadside against Harry Wu, a naturalized American who immigrated from China after spending 19 years in prison camps, in a report by the official Xinhua news agency and a videotape of his purported confession.

The grainy black-and-white footage of ``See the Lies of Wu Hongda,'' titled after Wu's Chinese name, provides one of the first glimpses of the activist since he was detained 5 1/2 weeks ago.

Wu, 58, sits in an armchair, his head bowed, hands nervously clasping and unfolding. In the small room, two police officers sit in front of him and two others flank him.

One of the officers asks Wu about two documentaries he made for the British Broadcasting Corp. last year on forced prison labor and the transplanting of organs from executed prisoners.

While Xinhua claimed that Wu admitted he intentionally made errors editing and scripting the documentaries, the videotape shows him putting much of the blame on the BBC.

``Who edited the commentary?'' the policeman asks.

``The BBC,'' Wu replies, his chin pressed against his chest.

The interrogator asks if the report has ``any foundation.''

``I've said it's wrong,'' Wu says.

In London, the BBC said it stood by the reports.

Much of the confession _ including Wu's acknowledgement that he lied about his identity and that hidden cameras were used _ was made clear in the reports, which were shot in April 1994.

State Department spokesman Nicholas Burns told reporters in Washington Thursday that ``everybody understands the conditions under which such tapes are made.''

``Harry Wu has been a tireless advocate of human rights,'' Burns said. ``He has spoken very clearly under adverse circumstances about human rights problems in China. And therefore we would look at such tapes with a great deal of skepticism.''

Wu's wife, Ching-lee Wu, scoffed at the video.

``I think it's a joke,'' she told The Associated Press by telephone from her home in Milpitas, about 40 miles outside San Francisco. ``Harry worked very hard on making all the information accurate, and that's why China is trying to discredit him and his work.''

She said her husband looked ``terrible.''

``He looked very tired, and I think he lost at least 10 pounds,'' she said. ``I feel very sad.''

Neither the videotape nor the Xinhua report give any indication of how long Wu had been questioned before the confession, nor when or where the interrogation took place.

The 13-minute video, sold by an ostensibly private Chinese company to several Western news agencies for $3,000, contains the interrogation interspersed with excerpts from the BBC documentaries.

The prison labor documentary showed leather jackets, children's clothes and other goods being sold outside a prison, and asserts the goods were made by prisoners _ as are half of northwestern China's exports. The Chinese government denies the charges and said there was not even a prison near the market shown.

Wu purportedly agreed that those things were incorrect and blamed the BBC for introducing them into the report, as well as for reporting that footage of a cemetery showed prisoners' graves when the graves did not belong to prisoners.

Wu also admits in the video that he ``deceived people'' during a visit to a medical university. He and BBC producer Susan Roberts posed as married scholars from Tuscaloosa, Ala., looking into a kidney transplant for a sick uncle.

``None of the doctors told me the kidneys were from condemned prisoners,'' Wu says in the videotape. ``All said they were from brain-dead patients.''

Backing up the government's claims are lengthy interviews with hospital staff recounting Wu's visit and disputing the BBC report.

In its response, the BBC noted that the videotape did not show Wu denying the main points of the reports.

``In the tape released by the Chinese, Harry Wu is clearly under duress during hostile cross-examination,'' a BBC statement said. ``The BBC stands by the reports. ... (We) are satisfied that it complies with all the BBC's editorial standards.''

After emigrating to the United States following his release from prison in 1979, Wu dedicated himself to uncovering the abuses of China's vast penal colony. He has returned to China several times since 1991 for that cause.

Since he was detained June 19 trying to enter China from Kazakhstan, Wu has had only one meeting with U.S. officials, on July 10 in Wuhan. Two days earlier he was formally arrested for spying, a charge that carries a penalty ranging from three years in prison to death.

U.S. Embassy officials declined comment on the alleged confession, but said they were still seeking increased access to Wu. A consular agreement allows only for monthly visits.

The Clinton administration has called for Wu's immediate release. His detention has strained Sino-U.S. relations at a time when ties were already frayed by disputes over Taiwan, trade and arms sales.

Wu's case is now under ``investigation,'' a period before indictment which usually involves lengthy interrogation.

China's often intentionally opaque legal system places great stock in defendants acknowledging their mistakes. It was not clear if Wu's admissions would meet the government's demands.