Agents for the FBI and Naval Investigative Service videotaped Deputy Assistant Air Force Secretary Victor Cohen and other Pentagon officials accepting alleged payoffs from defense consultants, federal law enforcement sources said Friday.

The sources also said James Gaines, a deputy assistant Navy secretary, was videotaped meeting with consultants during the two-year investigation of alleged bribes-for-confidential contract data that became public last week.Investigators suspect Gaines to be the primary supplier of classified or confidential data for his former boss, Melvyn Paisley, who became a consultant for the McDonnell Douglas Corp. and other companies, according to these sources.

But sources said others among the six Defense Department procurement officials who were reassigned by Defense Secretary Frank Carlucci this week pending the outcome of the investigation also are suspected of taking kickbacks.

NBC News, which first disclosed the evidence against Cohen, quoted sources as saying that whenever a defense consultant would phone him at his office he would "clear his calendar" and leave the Pentagon.

The network also reported - and law enforcement sources confirmed - that Cohen's meetings were "recorded and videotaped, and money changed hands."

The sources told United Press International that Cohen, a former consultant for the Northrop Corp. who oversaw contracts on classified tactical programs, had previously been the subject of a separate inquiry by California investigators for the Pentagon's inspector general's office into alleged leaks of sensitive documents.

That investigation found insufficient evidence to prosecute Cohen, but he was made a subject of the FBI-NIS investigation about a year ago, when the wiretaps began, the sources said. Results of the earlier investigation were reported to Air Force Secretary Edward Aldridge Jr. and to the Pentagon's general counsel, Kathleen Bucka.

Law enforcement sources said investigators later learned the results of the first inquiry had filtered back to Cohen.

"He bragged about (earning) it to a consultant," a source said. "He was unaware the taps were in place on the other investigation."

Cohen's lawyer, Seymour Glanzer, could not immediately be reached about the allegations but has declined to comment to date.

Sources have said that industry consultants often sold information, including competitors' bids, on the same defense program to several competing companies. NBC quoted an investigative source as saying that the losers did not complain because "if the companies didn't play ball, they lost."

The network said that to conceal huge consulting payments from government auditors, defense contractors commonly asked them to submit "meaningless research papers," submitting the same paper as many as 16 times and collecting in each instance.