D.C. Del. Walter E. Fauntroy and two other black leaders were released from jail yesterday after pleading innocent in D.C. Superior Court to charges of unlawful entry in a sit-in at the South African embassy here late Wednesday.

Looking tired after nearly 20 hours in police custody, Fauntroy and codefendants Mary Frances Berry, a member of the U.S. Civil Rights Commission, and Randall Robinson, director of TransAfrica, a black lobbying group, were released on their own recognizance.

Superior Court Judge Bruce S. Mencher set Dec. 20 for a pretrial hearing in the case.

Fauntroy, Berry and Robinson were removed by uniformed U.S. Secret Service officers at the request of the embassy after the three refused to leave a meeting with Ambassador Bernardus G. Fourie. The group was discussing the fate of black South African labor leaders who were jailed without charges during recent unrest in that country.

"Ours was an act of conscience in response to the repressive action of the South African government with respect to the noble, nonviolent protests of black South Africans over the last few months," Fauntroy told a news conference after his release about 2 p.m. yesterday.

Robinson said the sit-in was intended to focus attention on the racial policies of "the world's most vicious government."

"There comes a time when you have to bear witness," said Berry, against the "immorality" of the South African regime. "It is true that time is running out there."

The three declined to answer questions from reporters. TransAfrica, the lobbying organization, has scheduled a news conference for 11 a.m. today at the Rayburn House Office Building. Robinson said the group will detail plans to escalate its protest activities nationwide in the coming weeks.

No trial date was set yesterday for Fauntroy, Robinson and Berry. Unlawful entry is a misdemeanor punishable by up to six months in jail and a $100 fine.

The three could have been released Wednesday evening after they had been booked by police, but refused. Fauntroy and Robinson spent the night in the central cellblock at police headquarters. Berry was taken to D.C. Jail in Southeast.

Fauntroy, 51, said he was able to get some sleep on a steel bunk in his cell.

Among the spectators at yesterday's arraignment were Rep. Charles Rangel (D-N.Y.) and Eleanor Holmes Norton, a former chairman of the Equal Employment Opportunity Commission and now a Georgetown University law professor. Norton joined in the talks at the South African embassy, but in a planned move left before the arrests.

The Associated Press reported from Pretoria that Ambassador Fourie requested police assistance in clearing the embassy after conferring by telephone with South African Foreign Minister R.F. Botha.

Christiaan C. Badenhorst, an embassy information officer, said yesterday the embassy had no further comment on the incident.

The U.S. Attorney's office here had the option of dropping the charges before the arraignment, but elected to proceed with the case after prosecutors were unable to contact anyone at the State Department or the embassy, a senior official said.

The official said it was standard procedure to go ahead with charges when prosecutors are unable to contact the victim of an offense immediately. The charges could be dropped later if the State Department or the embassy requests it, the official said.

TransAfrica, which has its national headquarters at 545 Eighth St. SE, is a black American foreign policy lobbying organization with an emphasis on Africa and the Caribbean, director Robinson said in an interview. He said the 7-year-old group has 10,000 members in 12 chapters across the country.

"It is the mechanism through which black Americans express their views to Congress and the administration," Robinson said.