Federal agents have found the names of some of the Unabomber's victims in documents seized during a search of the primitive Montana cabin of Theodore J. Kaczynski, adding to the weight of circumstantial evidence that authorities believe will allow them to charge the former math professor with the attacks, senior law enforcement sources said yesterday.

The sources said the names, which they would not disclose, were not in the form of a list but were contained in written or published material that they declined to characterize.

Earlier, authorities found a typewriter possibly linked to writings by the elusive Unabomber, as well as bomb-making chemicals. On Friday, federal agents combing Kaczynski's one-room cabin found, under his bed, a complete bomb similar to those used in the Unabomber's 17-year string of attacks. They also have established that Kaczynski, traveling by bus, had visited the Sacramento area around the time of at least one Unabomber attack linked to the city.

Kaczynski, a former assistant professor at the University of California at Berkeley who quit and became a mountain recluse, has been charged only with one count of possessing bomb-making components. A federal grand jury will convene in Great Falls, Mont., April 17 to hear the case.

Three people were killed and 23 injured in Unbomber attacks that began in 1978. The FBI has run a massive manhunt for the Unabomber for years, but the key break in the case came only in January, when Kaczynski's younger brother noted similarities between Unabomber writings and his brother's and had a lawyer contact the FBI.

"Sacramento is hot, a very promising area so far," said one official involved in the case. San Francisco and Salt Lake City, where bomb attacks also took place, are two other areas of intense focus, as FBI agents, U.S. postal inspectors and Bureau of Alcohol, Tobacco and Firearms agents continue the federal probe, attempting to reconstruct Kaczynksi's life over the last few decades.

In addition, federal agents were focusing considerable attention on how the Unabomber picked his targets. Yesterday they continued to sift through the prodigious records stored in Kaczynski's cabin.

Last summer, long before Kaczynski's name came to its attention, the FBI began investigating whether the Unabomber used a so-called ecological hit list to select his most recent victims.

According to a report by ABC News last August, the list was printed in 1990 in an anonymous publication entitled "Live Wild or Die" and was made up of 11 companies and organizations said to be enemies of the environment.

Two targets stood out: the Timber Association of California and the Exxon Corp. In April 1995 the Unabomber mailed a deadly pipe bomb to the Timber Association, which years earlier had changed its name to the California Forestry Association, and in December 1994 he sent one to a public relations executive whose firm had done work for Exxon.

The bomb sent to the Timber Association was addressed to William N. Dennison, its former head. But it killed Gilbert P. Murray, the new president of the Sacramento-based timber industry lobbying group, which had changed its name in 1992.

The public relations executive killed was Thomas J. Mosser, who worked for Burson-Marsteller, a firm that counted Exxon among its clients. The Feb. 2, 1994, edition of Earth First!, an outspoken environmentalist journal, carried an article attacking Burson-Marsteller and accusing it of promoting "an elite form of environmentalism' that serves the need of the corporate world."

The article, entitled "The International PR Machine," listed Exxon as one of Burson-Marsteller's clients and charged, erroneously, that Exxon had hired the firm "to counter the negative publicity from the Valdez oil spill." (Burson-Marsteller has said it did no work on the Alaska oil spill.)

Mosser died in the kitchen of his North Caldwell, N.J., home in December 1994. He had been promoted to Burson-Marsteller's parent firm, Young & Rubicam, months earlier.

Suspicions that the 1990 list may have been the origin for the Unabomber's last targets were voiced by a controversial private investigator named Barry Clausen. He told "ABC Evening News" that he got a copy of the publication from a member of Earth First! The group's officials said they knew nothing of the Unabomber and said the organization had an "unbroken, unblemished record of nonviolence." The FBI also is trying to determine whether Kaczynski might have attended environmentalist meetings such as one held in Missoula, Mont., a month before Mosser was killed. Hundreds of environmentalists attended the gathering to discuss opposition to multinational timber firms. Missoula is 63 miles from Lincoln, the small town nearest Kaczynski's cabin.