Washington's streets came out of hibernation Friday night. The weather hinted at spring, the work week had ended and it was what police call "Mother's Day," the first day of the month, when government payments such as welfare checks hit mailboxes all across the city.

For many, it was a night to party. But by the end of it six people were dead and nearly two dozen others lay in hospitals, some in critical condition, after taking what junkies call a "bomb" -- a heavy dose of heroin so potent that even a little can kill.

Last night the body of a seventh apparent overdose victim was found in a house in far Northeast, police said. It could not be determined if he was connected to Friday night's series of fatalities.

The victims were found in houses and on street corners, in apartments and at a shelter for the homeless. And their lives were as different as the locations where the ambulances picked them up.

The dead included a hard-working janitor and a D.C. college student whose younger brother is a policeman. There was a drifter from a close-knit family who had come home to Temple Hills a few weeks ago, saying he wanted to kick his drug habit. And there was a woman who walked into a shelter for the homeless last year looking for a place to sleep, and ended up staying to join the staff. She had stopped using drugs, or so her friends thought until yesterday morning.

For them, and for many others who used heroin on Friday night, the decision was a fateful one.

"People are falling dead out there in the street," said D.C. narcotics detective Larry Coates, "and there are people out there begging for some of this dope. It's insane and it's dangerous."

Police officials said that the heroin may be as powerful as any that has spread through the District in years. According to narcotics officers, heroin normally found on the street has a purity of about 2 percent. A level of 8 percent can be lethal. The purity of this heroin is believed to be about 12 to 14 percent.

By 10 o'clock Friday night, four hospitals scattered across the District, generally experienced in dealing with drug overdoses, were overwhelmed by a sudden rush of victims. Police and city officials said they are perplexed by the geographical range of the incidents.

"In one place, with one small batch this can happen," said a homicide detective. "But all around the city is scary."

Yesterday, every police narcotics unit in the city was on the streets, trying to stitch together the loose threads of Friday's ravages. And as they worked, the families and friends of the dead -- who had little in common but their grief -- tried just as hard to figure out what had happened.

On Friday night at the Committee for Creative Non-Violence's homeless shelter at Second and D streets NW, there had been a going-away party for one of the staff members, with guitars and singing, a movie, a puppet show and a lasagna dinner cooked by Deborah Claiborne.

Claiborne, 32, one of those killed by the heroin, had come looking for a home at the shelter a year ago. She was "bright and articulate, very together, but her drug problem has caused an alienation with her family," said shelter staff member Carol Fennelly.

Claiborne was "gifted . . . among the women who come in she stood out," and soon she joined the shelter's staff.

A few months ago, Claiborne went to Iowa to work at a soup kitchen. She wanted to "get away from people who would influence her" into using drugs, Fennelly said. "I suspect she did want to kick the habit, but it's easier said than done."

Everyone thought she had succeeded, and at last night's party "she looked great." But sometime after midnight, people at the shelter noticed that she was absent.

After breaking down a locked bathroom door, they found her collapsed in the stall. A short time later Claiborne was pronounced dead.

Lucille Ferguson returned to the family home at 845 Xenia St. SE to find her 29-year-old son, Harold Ferguson III, a student at the University of the District of Columbia, unconscious. A woman, unknown to the family, was there, too, also the victim of an overdose, according to a younger brother, police officer Lloyd Ferguson. Both victims were taken to hospitals. Harold Ferguson was pronounced dead at Greater Southeast Hospital.

"We were all stunned," Officer Ferguson said yesterday. "We couldn't believe it. Nobody can . . . . We never knew him to have a drug problem."

Virgie White tells the same story of her boyfriend, Henry Edwards, 34, with whom she had lived for two years at 1631 Euclid St. NW. "He took drugs a long time ago, not anymore," White said yesterday. She last saw him when he went out Friday evening, on his way to his janitorial job at 17th Street and Columbia Road NW. "Henry was a nice guy. His heart was always giving."

He collapsed in the basement of the building where he worked, and he died before White even knew he had been taken to the hospital. "He didn't do this to himself," she said. "I'm still trying to figure out what happened."

So was the Keeling family in Temple Hills. Lloyd Keeling said yesterday that he knew that his younger brother, Arthur, 28, was having problems when he arrived at his door a few weeks ago, asking if he could move into the home at 4553 Akron St. For several years, Arthur had "been wayward from us," drifting from job to job, calling only when he needed help, the elder Keeling said yesterday.

"This is all new to us -- drugs. Where he picked it up I don't know," Keeling said. "We've never been associated with that in our family."

On Friday night, a neighbor drove Arthur Keeling to a friend's house in Southeast and waited for him down the block, Lloyd Keeling said. Suddenly, the neighbor looked out the car's back window and saw Arthur collapse in the street. He rushed him to the hospital. By the time Lloyd Keeling arrived, "they were trying to revive him." But it was too late. Yesterday the Keelings were making funeral arrangments.

"He was the youngest of three brothers," Lloyd Keeling said. "So naturally I tried to help him, but I couldn't help him with drugs."

Yesterday, political leaders and city officials appealed to residents to refrain from using narcotics while they tried to find out more about the source of the drugs. As of early last night they had no suspects, but narcotics detectives were interviewing informants and trying to purchase samples of heroin on the street in order to test its purity.

D.C. Council member Wilhelmina Rolark (D-Ward 8), who represents far Southeast, where most of the drugs were sold and where several victims died, said yesterday: "I am making a broad appeal to those who are taking drugs to stop, and to those who aren't, not to try it. People must say 'no' to drugs. You may try it and die."

Medical personnel throughout the District were prepared last night for those who did not heed her warning.

"I promise you, if the stuff is still out there on the street tonight we'll have more dead," said Dr. Kenneth Larsen, chief of the department of emergency medicine at Greater Southeast Community Hospital. "This seems to be an explosive batch of heroin, and people want it."

Greater Southeast reported the first wave of narcotic-related deaths Friday night. Between 7:45 p.m. and 8:45 p.m., four people were rushed to the emergency room. Two died, and one has been kept alive only by the use of machines. The fourth victim was released.

"The staff had no time to reflect on what was going on in the city," said Amy Freeman, the nursing supervisor on duty at the time.

"We knew we had something rare, but it wasn't until later in the evening that we could think about it. By then, we were jumpy, in anticipation of more cases coming in."

The widespread confusion and apprehension continued yesterday.

"It was madness last night," said a spokesman for D.C. General Hospital. "And we don't know what to expect tonight."