WASHINGTON -- A select House committee, in a classified report unusual for its bipartisanship, has found that over the last 20 years China obtained, sometimes through theft, some of the most sensitive of American military technology, including nuclear weapons design, Government officials and witnesses before the panel say.
The committee's final report, unanimously approved by its five Republican and four Democratic members Wednesday, found that during Republican and Democratic Administrations alike, China acquired a range of technical secrets far beyond the satellite- and missile-related technology whose transfer by American satellite companies during the Clinton Administration prompted the start of the panel's inquiry in May.
In a carefully worded statement after the report had been approved, the committee's chairman, Representative Christopher Cox, Republican of California, said that China's acquisition of American technology had harmed national security and that its "acquisition efforts over the past two decades" had been a "serious, sustained" activity.
The panel's 700-page report is secret because so much of its six-month inquiry dealt with classified information, and it released no details from that report Wednesday.
It promised to begin a process, in consultation with the Clinton Administration, to declassify as many of the findings as possible.
But witnesses and intelligence officials who worked with the committee said it agreed with assessments by the Pentagon and the State Department that information shared with Chinese scientists by two American companies, the Hughes Electronics Corporation and Loral Space and Communications, had improved Beijing's ability to launch satellites and ballistic missiles.
In addition, witnesses said, the panel's conclusion that China had stolen military-related American technology may prove to be the most explosive part of the report.
The panel uncovered, for example, a pattern by the Chinese of stealing nuclear-weapons design technology from American nuclear laboratories, said one person who has read part of the report. It was unclear when or over what period of time any of these nuclear-related thefts might have occurred.
The committee, officials said, faulted policies of the Reagan, Bush and Clinton Administrations but did not say whether the problems were worse in one Administration than in another.
It made 38 recommendations for legislation or executive orders to address those policy failures. The recommendations covered policy categories like security at weapons laboratories, the handling of sensitive intelligence data and export controls.
While the committee did not directly examine covert Chinese contributions to the 1996 American election campaigns, officials said, it did investigate the activities of a Chinese aerospace executive, Liu Chao-ying. Ms. Liu was a conduit for Chinese Government payments to Democratic fund-raisers and, with her father, Liu Huaqing, formerly the senior general in the Chinese military, has been involved in Beijing's effort to acquire military-related technology.
The House committee began its inquiry in the spring after The New York Times had disclosed that American satellite makers had helped Chinese scientists rectify failures in their rocket programs, conveying information applicable to long-range ballistic missiles. Over the last six months, the panel held 33 hearings, all closed, taking testimony from intelligence officials, industry executives and nuclear-weapons experts.
The committee's inquiry initially focused on the interaction between China and the American manufacturers whose satellites were carried into orbit on Chinese rockets.
It soon branched out to examine the export of other American technology to China, including advanced computers and machining equipment.
The panel hired outside experts to examine whether scientists from Hughes Electronics, a subsidiary of the General Motors Corporation, and Loral Space and Communications had harmed national security by giving the Chinese lessons in rocket technology after the failure of two Chinese rockets in the mid-1990's.
Both companies deny any wrongdoing, but earlier this month the Administration completed reports of its own that raised national security concerns about the assistance, especially help that Hughes provided the Chinese in 1995.
The intelligence arm of the State Department found that the 1995 'tutorial" by Hughes "resulted in significant improvement" to China's rocket program and that the lessons were "inherently applicable to their missile programs as well."
In a news conference at the Capitol Wednesday, members of the committee said their analysis had gone far beyond the reviews of the failed Chinese rocket launchings involving Hughes and Loral.
"There was harm in some of the transfers of technology that occurred," said the committee's ranking Democrat, Representative Norm Dicks of Washington, "but it's also fair to say this is not the only problem we uncovered. These are serious problems that must be addressed by the Administration and by the Congress."
It is public knowledge that the Chinese have an aggressive military and economic espionage program and that they have long sought to acquire American technology, legally and illegally.
But the House panel, formally the Select Committee on U.S. National Security and Military/Commercial Concerns With the People's Republic of China, learned new details about the depth and scope of these activities as it completed the most comprehensive examination of the issue ever conducted by any part of the American Government.
The witnesses before the panel included officials from American nuclear weapons laboratories, one witness said. Last year the General Accounting Office, the investigative arm of Congress, issued a report that questioned the adequacy of security at the weapons labs, and touched on a decision during President Clinton's first term to reduce background checks of various foreign visitors there. (The visitors, most of whom are Russian and Chinese, are not allowed access to classified areas.)
It is unclear exactly how much the American public will ever learn about the committee's findings.
The issue of what to disclose is usually resolved by the release of general conclusions, and the withholding of details that might reveal how the sensitive information was acquired.
Any process in which the report is declassified would involve the Clinton Administration, officials at various intelligence agencies like the C.I.A. and the House of Representatives.
"Certainly we look forward to reading the report and studying its recommendations," said David C. Leavy, a White House spokesman. "In terms of declassification, we need to work with the committee and relevant agencies in an appropriate way to move forward."
That the committee could find political unity in a year of divisive discourse was probably due to the serious national security concerns that were the panel's work.
Other than Cox and Dicks, the members of the committee were Representatives Curt Weldon of Pennsylvania, Porter J. Goss of Florida, James V. Hansen of Utah and Doug Bereuter of Nebraska, all Republicans, and John M. Spratt Jr. of South Carolina, Robert C. Scott of Virginia and Lucille Roybal-Allard of California, Democrats.