A former employe of Hughes Aircraft Co. and a Polish national have been arrested in California in connection with the alleged sale of classified documents on U.S. weapons and radar systems, the FBI announced yesterday.

The FBI identified the two men as William Holden Bell, 61, until last Tuesday an employe at the Hughes plant in El Segundo, Calif., and Marian W. Zacharski, 29, president of U.S. operations of the Polish American Machinery Corp. (POLAMCO), headquartered in Elk Grove Village, Ill.

"For more than a year, Bell allegedly furnished classified Hughes Aircraft documents to Zacharski and other Polish intelligence service officers, and in exchange received cash payments totaling more than $110,000," the FBI announcement said.

"These highly classified documents were exchanged at locations in this country and Europe and pertained to U.S. military weapons and radar systems," the FBI said.

Hughes Aircraft is an important defense contractor, building battlefield missile systems and communications equipment, as well as satellite hardware.

The FBI would not elaborate on the number or types of documents allegedly sold by Bell, but a knowledgeable official, who characterized the incident as "very serious" referred to them as "state of the art" documents, containing the latest technology.

"Any case that involves classfied information is an important case," an FBI spokesman said, noting that Poland could be expected to share its intelligence with the Soviet Union, its ally under the Warsaw Pact.

Details on the arrested men and the alleged espionage operation were sketchy, but Zacharski was known to U.S. counterintelligence officials as a "rising star" in the Polish business and intelligence community. Dick Mellitt, an FBI counterintelligence agent, told a news conference in Los Angeles that Zacharski had been under investigation since his arrival in this country in 1977.

Mellitt said Bell, who joined Hughes as a line engineer in 1952, had been under investigation since 1978, with the cooperation of Hughes officials. Bell was fired last Tuesday.

Lee Pitt, communications director for the company, said Bell was a project manager and a member of the company's radar systems group. As such, he had secret clearance, which allowed him access to classified and secret documents, Pitt said, but he did not have top secret clearance, which would have given him access to the firm's most sensitive documents.

Bell traveled to Europe occasionally on company business, Pitt said, and worked in Hughes' office in Brussels from 1974 to 1976, the only time he worked outside of southern California.

Mellitt said the two men had known each other on a social basis since Zacharski's arrival in California, where he was until recently the West Coast manager of POLAMCO. The two men apparently met in the Los Angeles suburb of Playa del Rey, where they are residents of the same apartment complex. The arrests took place yesterday in Playa de Rey.

The two men were being held for arraignment today in federal court in Los Angeles. If convicted of espionage, they could be sentenced to life in prison.

Pitt said this was the first time any Hughes employe had been arrested for espionage in the 48-year history of the company, founded in the early 1930s by billionaire recluse Howard Hughes.

"We have 56,000 employes," he said. "We have one of the tightest security systems in the country." Pitt could not say how Bell, who he described as an efficient employe with a blemish-free record, had managed to frustrate that system.

The most recent similar case involving the transfer of sensitive material from a defense contractor to a foreign government is that of Christopher Boyce, a college student employed in a code room operated for the Central Intelligence Agency by TRW Inc. in California. Boyce was convicted of passing information to the Soviet Union through a friend, Andrew Dalton Lee. Both were convicted, and Lee is serving a life term at the Lompoc penitentiary in California. Boyce escaped from Lompoc 18 months ago and is still at large.

The last espionage charge in the United States was filed last October against David Henry Barnett of Bethesda, a former CIA agent who pleaded quilty to giving details of a 1960s' CIA operation in Indonesia to the Soviets, revealing the names of 30 CIA agents in the process. He was sentenced to 18 years in what the Justice Department said at the time was the 13th spy case in five years.