In the elevator of an apartment building here the other day, a local civil rights leader, the Rev. Bennett Smith, a tall and broad-shouldered black man, found himself unexpectedly alone with a white man he did not know.

"It was uncomfortable," Smith said later, recalling how they had watched one another warily and nervously as the elevator slowly rose 10 floors. "I was afraid of him and he was afraid about what I might do to him."

This gray and chilly fall in Buffalo there is fear, suspicion and some bold outpourings of racism. Even the chance encounter of a white man and a black man in an elevator can be an unnerving event, something mostly everybody here acts scrupulously to avoid.

In apparently random murders in late September, three black men and a black teen-ager were shot and killed in a period of 36 hours with the same .22-caliber gun. Witnesses told police that a white man of medium height with light hair had shot all four in the head at point-blank range. Less than two weeks later, the brutally beaten bodies of two black cab drivers were found with their hearts ripped out.

"Everybody's looking over his shoulder," said James Pitts, one of six black members of the 16-member Buffalo Common Council. "If you talk to cab drivers, folks who hang on the streets, they're armed. You fear for your safety. It's a fear that I'm out there by myself."

Pitts said he carries numchucks, a lethal weapon consisting of a chain suspended from two wooden handles. Rev. Smith carries a .38-caliber revolver, which he said makes him and his wife very uneasy.

Few black men venture far from the presumed safety of the sprawling ghetto here at night. Mozella Richardson, one of three black members on the nine-member Buffalo School Board, laughed in sharp, short nervous bursts as she talked about her efforts to keep her teen-age son close to home.

"My son asked me the other day, 'Shouldn't everybody be treated equally?' I said, 'Yes, but what you're going to find out is that's utopia.'"

Buffalo, a friendly place: that is what they say on the radio and television and in the newspapers here as the city conducts a multimillion dollar campaign to boost its image. Begun before the murders, the first phase of the campaign is aimed at Buffalo residents themselves. It is an effort to shake this city's inferiority complex, which has been aggravated by the many jokes over the years about Buffalo. A character in the Broadway play, "Chorus Line," talked about once considering suicide in Buffalo, then deciding that would be redundant.

A tough, blue-collar steel and railroad town on Lake Erie with tight knit Polish, Irish and Italian neighborhoods, bitter winters and a well-entrenched Mafia, Buffalo had its heyday during World War II when the war plants here were booming and thousands of blacks migrated up from the Carolinas, Georgia and Alabama for the jobs.

Life has never been so good since. This city has lost jobs and population at a rapid clip. Like many other northern industrial cities Buffalo is fighting with the Census Bureau over just how many people moved away in the last decade. Census said there are about 357,000 people here, nearly half the number there during the war. It is estimated that blacks are now about a third of the population.

Overall today, unemployment hovers around 10 percent. It is double that in the black community of little brown and gray shingle and frame houses, storefront churches and bars with names like The New Breed that spread north and east from downtown.

There are some signs though that the city may be coming back. A few new squarish brown and gray office high rises tower above the old buildings downtown. There are plans to develop the waterfront with restaurants and condominiums and some Kuwaitis have taken an interest in the fading old Statler Hilton where many of the rooms have been converted to offices but you can still easily get accommodations for $22 a day.

Mayor James Griffin, who was elected on the Conservative Party line in a tough law-and-order campaign three years ago, is concerned that national press accounts of the murders will give the city "a rap it doesn't deserve." He emphasizes that only two of the murders occurred within the city's limits, the others in the outlying suburbs.

"There's a heck of a lot more murders taking place in Atlanta, Ga., than in the city of Buffalo," he told a reporter.

He said he believes the black community has been stirred by its leaders to needless alarm, recalling that there was no huge community outcry when a few years back a black man raped and killed four white women.

"The white community wasn't up in arms, saying we ought to arm ourselves," he said.

The press here has had a field day with the story, drawing inexact comparisons between the murders of the black men and the Son of Sam killings a few years back in New York City. The other day, the morning newspaper, the Courier Express, ran this headline: "Profile of Killer: Loner, Filled with Hatred, Will Strike Again." Underneath was a modest story, reporting the opinions of two psychiatrists, one on the faculty of a local university, the other unidentified.

Local television station WKBW has referred to the killer of the cabdrivers as "Jack the Ripper" and in a promo for one late evening newscast on the police search for the cab drivers' assailant urged viewers to stay tuned for a report on "hunting the hacky hacker." WKBW has filled out the drama by paying to fly in an astrologer, a psychic and black spokesman Jesse Jackson to aid police and calm the black community -- after they have been filmed by the station, of course.

There have been a range of reactions to the murders among whites in Buffalo. Religious leaders and newspaper editorial writers have deplored the killings, and the Chamber of Commerce has pledged $25,000 for a reward for information leading to arrest and conviction of the murderer. The morning Courier Express pressed for a unity day rally that drew a crowd of about 5,000.

Elsewhere, however, the murders have met with indifference and some outright expressions of hostility toward blacks. Circulating through the taverns and doctor's offices here are jokes about the "Son of Sambo" killings and the need to establish a "heart fund" to buy a more powerful weapon for the murderer.

Civil rights leaders have received, anonymously in the mail, "one-way tickets back to Africa." A carload of white teenagers cruised by the storefront church where funeral services were being held for one of the victims. The head of a mannequin was mounted on the hood.

Douglas Turner, the executive editor of the Courier Express, was stunned by the hostile reactions at a big Irish dinner to the black ribbon pinned to his lapel, the symbol of mourning here.

A public official told him, Turner said, "this is what they've been waiting for over there. This is a real good break for those black leaders. This is an opportunity for them to get up on their soap boxes."

A clergyman Turner said he had known for years said of the murders, "Don't you know that's the only language those people understand?"

District Attorney Edward Cosgrove said he has a 185-member task force investigating the numerous tips received in connection with the slayings.

He said investigators have no solid leads that would enable them to make an arrest but he rules out the speculation of black leaders that the murders may have been inspired by the Ku Klux Klan, which was briefly active here three years ago. Cosgrove told black leaders that "no self-respecting Klansman" would be involved in the murders, raising questions in their minds about his investigation.

"I said no self-respecting Klansman that I knew of -- having been an FBI agent investigating the Klan in the 1960s -- would have anything to do with this kind of activity," Cosgrove later explained to a reporter, expressing surprise that his remarks had touched off adverse reactions."What I was trying to do was to assure them that I knew something about the Klan."

Black leaders have demanded, and received assurances, that the FBI and local U.S. attorney will also investigate the murders.

Meanwhile, Councilman Pitts, Rev. Smith and other black men in Buffalo move about the city uneasily.

"It's not a good feeling to have to walk around with a 'piece' [gun] on your side or in your car," Rev. Smith said. "My wife is nervous. I'm nervous. We pray for the day when we can put it away."