The late FBI director J. Edgar Hoover personally authorized "black-bag" jobs or surreptitious entries by FBI agents in 1970 during a hunt for Weather Underground fugitives in New York City, a former top FBI aide has testified.

The grand jury testimony of former FBI associate director William C. Sullivan was disclosed at a court hearing here yesterday by an attorney for former FBI director L. Patrick Gray and former assistant FBI director W. Mark Felt have been charged with conspiring to violate the civil rights of friends and families of Weather Underground fugitives by ordering a series of break-ins and allegedly illegal wiretaps in New York City in 1972 and 1973.

The attorney, Thomas Kennelly, said his client had the right to rely on the authorization of similar burglaries by Hoover in the same case in 1970 as well as the "customs and practices in the bureau" for such black-bag entries.

In addition, Kennelly presented as a witness another former FBI section chief who testified that he was present when Miller told then-acting FBI director William D. Ruckelshaus in 1973 that the FBI had conducted "black-bag" jobs under Gray.

The witness, Thomas V. Smith, said the men were discussing alleged FBI abuses when Ruckelshaus asked, "What else have you guys done?"

Millar replied, according to Smith, that "we had some bag jobs while Mr. Gray was here."

Ruckelshaus' response was "Oh my God," or something like that, Smith continued.

Kennelly argued that the case should be dismissed because government officials knew about the breakins in 1973 and did not bring charges until 1978 - a five-year pre-indictment delay that he says makes it difficult to properly defend his client because of the death of Sullivan and other key witnesses.

Kennelly also presented, under seal, to the judge 10 exhibits fr om FBI files - some highly classified - that he said show that former acting attorney general Robert Bork, former FBI director Clarence M. Kelley "and other officials at the highest levels of Justice or the FBI" knew about the surrepitious entries in 1973 and did "nothing about it."

Earlier yesterday, Gray's attorney said that the three former top FBI aides charged in the conspiracy "will slice each other to ribbons" if they are forced to go to trial together.

Alan Baron, representing Gray, said Gray will be in "direct head-to-head antagonism" with Miller because Miller claims the break-ins were authorized by Gray. Gray has denied the allegation, Baron said.

U.S. District Court Chief Judge William B. Bryant said he will rule later on the series of pretrial defense motions argued before him yesterday.