THE INTERSECTION of 14th and U streets NW - the crossroads and nerve center of black Washington in the 1960s - was filled with people changing buses, shopping or just hanging out when the news spread on Thursday evening, April 4, 1968: The Reverend Dr. Martin Luther King Jr. had been shot to death by an unidentified white assassin in Memphis, Tennessee. In the first minutes of shocked silence, the atmosphere at 14th and U became, in the words of one witness, "ominous - like before a hurricane strikes."

Inside the busy Peoples Drug on the northwest corner of 14th and U, customers gathered around a transistor radio at the camera counter heard President Lyndon B. Johnson mourn Martin Luther King and plead with the nation to "reject the blind violence that has struck Dr. King, who lived by nonviolence. But his words rang hollow to many blacks listening in the store. "Honkie," muttered one man. "He's a murderer himself," said another. "This will mean one thousand Detroits."

Suddenly, a group of about thirty people burst into the drug store. "Martin Luther King is dead," they shouted. "Close the store down!" As they herded customers through the aisles to the door, the man leading them, 26-year-old Stokely Carmichael, sought out the store's white manager. "It's closed," Carmichael told him excitedly. "It's closed." The manager did not argue. The store emptied and its fluorescent lights flickered out

Carmichael, the former national chairman of the Student Nonviolent Coordinating Committee (SNCC), had come to Washington to organize a "Black United Front" of local activist leaders. When he heard about the shooting in Memphis that evening, he went first to the Washington headquarters of Martin Luther King's Southern Christian Leadership Conference (SCLC) in a high-ceilinged old bank buidling just next door to the Peoples Drug. After talking by telephone to SCLC people in Memphis, Carmichael walked two blocks north on 14th street to the storefront Washington office of SNCC, where he rounded up a number of SNCC workers who gathered there. "They took our leader off, so out of respect, we're going to ask these stores to close down until Martin Luther King is laid to rest," Carmachael told them. "If Kennedy had been killed, they'd have done it. So why not for Dr. King?"

Carmichael and a growing group of teenagers and young adults then moved down 14th street, closing stores, carryouts, barber shops and movie theaters. Just south of 14th and U, the swelling crowd encountered Walter Fauntory, who was then an SCLC official and the chairman of Washington's newly appointed City Council. (He is now the District's delegate to the House of Representatives.) Catching up with Carmichael, Fauntory grabbed him by his arms and told him, "This is not the way to do it, Stokely. Let's not get anyone hurt. Let's cool it."

Carmichael, a foot taller than Fauntory, shook himself free and kept going. "All we're asking them to do is close the stores," he told Fauntroy. "They killed King."

Deciding that Carmichael's march might be a "useful channel of frustration" for the growing crowd he was leading, Fauntroy headed back to the SCLC office. He stopped along the way to tell a plainclothes policeman watching from an unmarked car that he thought everything would be all right. Fauntory advised against bringing un uniformed officers because their presence might provoke seroius trouble.

Only two nights earlier, outside the same People Drug at 14th and U, Stokely Carmichael and a Plainclothes police lieutenant had successfully dispersed a large, angry crowd that had stoned police who responded in force to a reported disturbance there. While Carmichael calmed the crowd, the lieutenant ordered the uniformed police to leave and then stayed behind himself to listen to the citizens' complaints. Similar brushfires had flickered frequently in Washington following shootings and heavy-handed arrests by police in black neighborhoods, but the city had this far avoided full-scale riots those suffered earlier by Los Angeles, Detroit and Newwark.

The crowd Carmichael attracted along 14th street after Martin Luther King's assassination soon grew out of his control, however. The first window was broken by a teenager at the Republic movie theater, just west of 14th street. While Carmichael was pulling the youth away, others on the fringe of the big crowd began kicking in windows at the Peoples Drug back on the corner. Then a middle-aged man who, with tears in his eyes, was loudly denouncing the white man's evil, picked up a street trash can and threw it through the drug store window.

"This is it, baby," someone shouted above the crowd. "Thes - is going to hit the fan now . . . We oughta burn this place down right now. . . Let's get some white m-. . . Let's kill them all."

"You really ready to go out and kill?" Carmichael shouted back. "How you gonna win? What you got? They've got guns, tanks. What you got? If you don't have guns, go home. We're not ready. Let's wait until tomorrow. Just cool it. Go home."

Then Carmichael heard what sounded like gunshots a block away on 14th street. The windows of Sam's pawnbrokers and Rhodes Five and Ten were being smashed. Dozens of people were reaching and jumping through the broken windows to grab watches, jewelry, radios and television sets. It was 10:24 p.m. The looting had begun and police headquarters downtown received the first trouble calls.

While looters carrying by him appliances, clothing and other booty streamed by him, Carmichael ducked briefly into the doorway of SCLC headquarters. He then dashed across the street and into a waiting car that sped off. The crowd had no leader now. All restraint was gone.

By 11 p.m. windows up and down 14th street being broken as hundreds of looters swarmed from store to store, cleaning them out. The youths dodged police, who had arrived and started chasing them with night-sticks, and threw stones and bottles at firemen, who had come to fight fires started in several parked cars and a handful of looted stores.

Finally, police used tear gas to break up th crowds and then ran down and arrested as many looters as they could. One of the 200 they caught was a 19-year-old carrying seven hats from the London Custom Shop. After watching a television news bulletin about the King shooting at his grandmother's house a few blocks away, he had come down to 14th street to see "what would happen."

By 3 a.m. Friday, police lined 14th street for twenty blocks. Windows had been broken in 200 stores, a few as far away as Hecht's at 7th and F streets downtown and D.J. Kaufman's nearby men's store on Pennsylania Avenue. More than 150 stores had been looted along 14th street and seven had been burned. Appointed Mayor Walter E. Washington and Police Chief John D. Layton left their temporary command post at the old Thirteenth Predinct stationhouse to announce that everything was now quiet. "The crisis is not over," Washington told reporters. "It's still out there, but the police have it well in hand."

If more trouble occurred, they figured, it would not be until Friday night. So Layton sent the police civil disturbance unit home to rest until 5 p.m., and Mayor Washington asked federal officials to have the D.C. National Guard and federal riot-trained troops on alert for Friday night. Chief Layton said he saw no reason to cancel the rest of the week's Cherry Blossom festivities or the parade scheduled for Saturday.