D.C. police searched for suspects yesterday in an early morning attack that left four men dead and two seriously wounded at a Northwest nightclub -- one of the deadliest outbursts since drug-related violence began sweeping the region in recent years.

Police said that two men armed with handguns entered the nightclub about 1:30 a.m. yesterday, apparently seeking to kill one person, 20-year-old Robert Lee Walker of the District.

After the two gunmen shot Walker, they turned and shot their way through a crowd of patrons who, a police spokesman said, the gunmen might have thought were blocking their escape.

Five others fell with gunshot wounds. Two died in the doorway of John's Place, a nightclub in the 1700 block of Seventh Street NW in the Shaw neighborhood. Another victim died about 40 feet from the club's entrance on a steel plate covering the street, which is broken up by construction of Metro's Green Line.

Sources said police were still searching for the motive but said Walker, who lived in the 1100 block of Ninth Street NW, was apparently the sole intended target. Police as of yesterday had not released the identities of the other three slain men, saying relatives had not yet been notified.

Even though the region's homicide rate has spiraled upward during the last three years, the attack was extraordinary for the number of people killed and wounded.

In January 1988, five people were shot to death in a Landover apartment. In January 1989, three people were fatally ambushed in a van in Northeast. Both incidents were drug-related.

Yesterday's killings brought the District's homicide total this year to 83, compared with 84 at the same time last year.

One of the two victims who survived the attack was released from the hospital yesterday.

Robert Bentley, 25, of Oxon Hill, was released from Howard University Hospital after being treated for a gunshot wound in the back, officials said.

The other survivor, identified as Michael L. Anderson, 26, of the 400 block of Delafield Place NW, was reported in serious but stable condition at the Washington Hospital Center's MedStar unit. A relative said that Anderson had been shot in the right calf, the foot and the arm, and that a bullet also had grazed his hip.

Anderson's brother, Subbi Tyrone Johnson, 25, said that Anderson regularly went to the club on the weekends to dance. Johnson said his brother, who did not know Walker, ran for the door when the shooting began and was hit when the gunmen sprayed the area near the door with gunfire. "He's upset because he didn't know what all of this was about," Johnson said.

Maurice Vaughn, 23, a friend of Walker's, said he and Walker were with about five other friends in the nightclub waiting for a slow-dance record to end. "Nobody wanted to slow-dance," Vaughn said. "I seen this guy pull out a gun and just fire a shot. My first instinct was to move out of the way.

"When all the shooting had cleared, {Walker} was on the floor. I just kept talking to him, telling him to hold on. He just had a blank look on his face."

Walker, who was shot just below the heart, was taken to Howard University Hospital, where he was pronounced dead about 7:30 a.m.

One of the shooting victims in the doorway apparently was armed with a handgun, one police source said. However, it was unclear immediately whether he had a chance to shoot it, the source said.

Police arrived within minutes of the shootings. They found chaos, with terrified people streaming out of the packed club, a police official at the scene said.

"People were running out of there. We tried to keep as many of them inside to interview them," the official said. Police quickly sealed the club, not letting anybody out until they had been interviewed. Police were still interviewing peo inside the club shortly before 4 a.m.

A 45-year-old man who did not want to be identified, but who said he cleaned the floors in the club, said he was standing at one end of the club when people started screaming and running, while others hit the floor.

The man said he stood aside as others poured out the door. "No point in running when you're that close," he said. "I learned that years ago. You don't know where you're running to."

The modest-looking nightclub sits at the end of a block known for drug trafficking, primarily crack cocaine. Much of the area is being torn down and is gated off because of the Metrorail construction.

The club used to be frequented by an older crowd, but in recent years has become a popular hangout for people in their early to mid-twenties, police said. One area resident said the club often stays open until 4 a.m.

Though drug dealers are among those who frequent the club, the nightspot has generally not been the site of violence, said one police investigator. "It's not the best place to off somebody," he said. "Everybody there is from the neighborhood and knows everybody else."

Yesterday, several people walked past the club talking about who had been killed and what they saw. They stepped over bloodstains as they made their way to the locked club to find purses and coats they had left behind when the shootings began. "I heard Coco was killed," a boy said, as he bought a soda in the store across the street.

Walker, whose nickname was "Coco," was a suspected drug dealer who ran with a rough crowd, a detective said.

A woman, who had come to retrieve her daughter's purse, said she knew Walker as he was growing up. "A lot of people didn't like him," said the woman, who did not want to be identified. "I say live by the sword, die by the sword."

Walker's mother, brother and best friend, sitting around the dining room table in Walker's home two blocks west of the club, said Walker was concerned about the streets in his Shaw neighborhood where he spent all his life. They said Walker, with friends, started a football and a basketball team for youngsters 16 and younger to keep them off the street.

"They were working to keep young kids from getting in trouble," said Walker's brother, Willie James Walker, 22. "He didn't want to see them keep catching juvenile charges. He didn't want to see them get shot up over somebody's car."

They said Walker spent a lot of time with his girlfriend and two children, ages 4 and 2. Saturday morning was Walker's second visit to John's Place. He was simply in the wrong place at the wrong time, they said.

"He left out of the house last night and said he'd be right back," said his mother, Martha Walker. "I told him to stop at the store and get some soda for the kids . . . . I feel terrible because he got shot and killed. They just come in shooting other people's kids."

Now two of Martha Walker's three sons are dead. Her oldest son, Thomas Lee Watts, died at the age of 20 in the Lorton Correctional Complex while he was serving time for armed robbery. He was stabbed 11 times. "I'm the only one left," said Willie Walker.

Mark Irving, 23, one of Robert Walker's friends, said that with "so many young black guys getting killed . . . it's not a surprise . . . . You wonder sometime when it's going to come to an end. Why did it have to be him?"