China systematically violates human rights in Tibet through arbitrary arrest and imprisonment, torture and abortions performed without the consent of the mother, according to a report released yesterday by a Washington-based human rights group.

In a 74-page report, Asia Watch describes "a system of repression" in which Chinese authorities frequently arrest political activists who support Tibetan independence. It says torture is commonplace during interrogation, and, according to one Tibetan quoted in the report, "If one speaks forcefully, if one gives an account of Tibet as being independent, they apply cattle prods."

China annexed the strategic region in central Asia more than three decades ago, but relations between Tibetans and Chinese civilians and troops stationed there have been strained.

During anti-Chinese protests last fall in the Tibetan capital of Lhasa, at least six persons were killed, most of them by police gunfire. Tibetans interviewed by Asia Watch said at least 19 persons died in custody as a result of injuries received after their arrest.

Chinese actions in Tibet have been criticized by U.S. congressmen, and the issue of human rights in Tibet has become an irritant in Beijing's relations with Washington. Assistant Secretary of State Richard Schifter, in presenting the State Department's annual report on human rights Wednesday, noted "some regression" in suppression of unrest in Tibet.

China has dismissed western criticism of its policies as interference in its internal affairs. Authorities have accused the Dalai Lama, the exiled Tibetan spiritual leader, of provoking anti-Chinese protests.

Zheng Wanzhen, press counselor at the Chinese Embassy, said the report was inaccurate in its depiction of "the actual political status, the relationship between the Han {Chinese} and the Tibetans as well as the political and economic development of Tibet." He added that some of the sources cited in the report were "questionable."

The report is based in part on interviews with private citizens in Tibet last year before and after the fall demonstrations, said Eric Schwartz, the group's program director. China turned down a request by Asia Watch to send a delegation to Tibet last October.

Although the report notes that the Chinese have permitted the reconstruction of Buddhist monasteries and allowed monastic ranks to grow in recent years, the Chinese still control the financial management of monasteries and regulate the numbers of monks in various monasteries.

Under China's family planning policy, minorities, such as Tibetans, are not limited to one child per family as most Chinese are. But according to the report, a two-child limit is applied strictly.

One source quoted in the report said: "If a woman is in a hospital and in the course of an examination {it is determined that she is pregnant,} the child is aborted. She is given medicine and an abortion is done without her even being asked. If a woman still wants to have a {third} child she can be given such medicine in the course of an examination for an illness. She doesn't know what the medicine is for . . . . This was done to people whom I know personally."