Andrew S. Hoffman, 20, a George Washington University student, was walking past the B'nai B'rith national headquaters near Scott Circle yesterday when two gunmen grabbed him and dragged him inside. Four other men, he said, were waiting there with guns and long machete knives concealed in musical instrument cases.

Hoffman said he was beaten by his assilants and forced to help them carry the weapons and boxes of amunition from the first floor to the third floor.

"They forced me to lay down on the floor with a large group of people," Hoffman said. "One man was forced to lay on top of me .He had been shot in the chest. Another man standing nearby had been stabbed. Blood dripped all over my pants." Blood dripped all over my pants." Hoffman's own blue jeans were spattered with blood.

Hoffman said the gunmen apparently liked him because he helped them carry their ammunition. "They asked me who my people were," he said. "I told them I was Italian and they let me go." Hoffman later told a reporter that he is actually half Jewish and half Italian and deliberately withheld the information about his Jewish background from the gunmen.

According to police, the gunmen who took over the headquaters of B'nar B'rith, the world oldest and largest Jewish service organization, were members of a black Muslim sect that staged similar takeovers yesterday at the Islamic Center and the District Building.

Police and B'nai B'rith officials said that more than 100 people were inside the B'nai B'rith building when six gunmen overpowered a guard in the lobby and entered the building.

Paul McKinney, a carpenter, said he saw one of the gunmen waving a pistol as McKinney was about to enter the elevator lobby of the building. McKinney said he left through a stairwell doorway and hid in the building's boiler room with three painters.

After hiding for about two hours, McKinney said, the four men got up their nerve and using McKinney's tools cut through a foot-thinck wire-mesh and plaster ceiling to the B'nai B'rith museum below where the police had set up an emergency communication headquaters.

It was not immediately clear how many of the people inside were being held hostage and how many were barricaded inside their offices, afraid to attempt to reach the outside.

Most of the people still inside the building were low'and middle-echelon employees who were manning the offices while many of the highest-ranking B'nai B'rith officials were attending a special luncheon at the Shore ham Americana Hotel for Israeli Prime Minister Yitzhak Rabin.

Both B'nai B'rith president David Blumberg and executive vice president Daniel Thursz attended the Rabin luncheon and were out of the building when the siege began.

One of the highest ranking officials remaining in the building was David Brody, Washington representative for the Anti-Defamation League.

Another official, B'nai B'rith assistant national membership director Harol Brenner, was also in the building, during the long afternoon but was released with 10 other persons at 6:20 p.m. by a police tactical unit sweeping the floors below the gunmen on the eighth floor.

According to a source at the American Jewish Committee, Brody phoned a lawyer and told his secretary that he would be unable to attend the Rabin luncheon because gunmen had just entered the building and he was sure he wouldnt' be able to leave.

Brody's call was made at 11:40 a.m., 15 minutes after the gunmen took over the building, indicating that he was not a hostage at that time, police said.

Shortly after the takeover, five wounded persons were allowed to leave the building. Steven Widdes, 26, of Arlington, who had been pistol-whipped, was treated for small lacerations to the head and release.

Wesley Hymes, 31, of 3500 B St. SE, was shot in the left arm and cut on the left hand with a machete. He was admitted to the hospital in fair condition.

Alton Kirkland, 22, of 1283 Brentwood Rd. NE was treated for stab wounds in the chest and back. He was reported in serious condition after surgery.

Michael Smith, of 4963 Morningside Dr., Dayton, Md., was treated for head injuries and released.

Brian Golliday, 12, was treated and released for head and back injuries sustained when he was struck with a gun.

According to Thursz, about 16 persons were released by the gunmen osme two hours after the siege began. "The only people released, to the best of my knowledge, were non-Jews," he said. He added that the people still inside the building were not all Jewish, and included whites, orientals, blacks and persons of various religions.

Throughtout the building, Thursz said, there were employees who barricaded themselves inside their offices to hide from the gunmen. He said four men working on a new wing of the building escaped throguh an air'conditioning duct.

B'rith official Brenner, after being released, told this story:

"The director of our insurance program was on our floor and his secretary called and said, "Please runsh down, there's a man with a gun."

"Then someone yelled, "Get away from the elevator. "The man with the gun is coming."

Brenner said the people in his office then moved quickly toward a larger office to barricade themselves. On the fifth floor. Eleven made it, but a 12th did not. From behind the door, which was baricaede with a file cabinet, Brenner said he heard a voice say, "OK, Me on the floor and spread-eagle." Then he said he heard a couple of muffled shots.

There was a phone in the room with a private line on it which did not light the buttons on any of the phones in the oter office occupied by the gunmen so they could get calls in and out undetected.

Brenner said they remained barricaded in the office from 11:30 a.m. until about 6:15 p.m. "We joked a lot and prayed a lot," he said.

He said the thing that frightened him most was that the intruders might be "placing some kind of a bomb" in the building.

Shortly before 6:15 p.m., Brenner said, the group heard a knock on the barricaded door. Next, a note was slipped under the door saying it was the police.

He said the group asked for a badge, but a voice said, "Believe me, I'm a policeman. Lie on the floor, don't move and open the door." A man in the group opened the door. Police officers then entered and took the group out a back entrance and down a ladder to freedom, Brenner said.

B'nai B'rith, founded in 1843 in New York City, is the oldest and largest Jewish service organization in the world , with 500,000 members in 46 countries. All but 75,000 members live in the United States.

The organization has programs in youth work, adult education, civic and veterans' services, career guidance, vocational counseling and inter-group relations.

Approximately 200 people work at the national headquaters of B'nai B'rith and B'nai B'rith Women, a separate organization located in the same building at 1640 Rhode Island Ave. NW. B'nai B'rith Women has membership of approximately 150,000 women, all but 10,000living in the U. S.

The membership of B'nai B'rith is organized into local lodges, including 20 in the Washington area. About 18 B'nai B'rith women chapters are located in the Washington vicinity.

The main organizations with B'nai B'rith are:

B'nai B'rith Organization, the largest Jewish youth movement in the United States, with 50,000 members in 1,638 chapters.

B'nai B'rith Hillel Foundations, which maintain religious, cultural and counseling centers at 242 colleges and universities in the U. S. and Canada and two broad. More than 180,000 Jewish students and faculty members participate in Hillel activities.

The Anti-Defamations League, organized in 1913 to monitor and combat anti-Semitism in the U. S. The ADL fights extremism and racial and religious prejudice against and the Jewish community as well as the other groups.