NEW ORLEANS » In the days after Hurricane Katrina left much of New Orleans in flooded ruins, the city was awash in tales of violence and bloodshed.

The narrative of those early, chaotic days — built largely on half-baked anecdote and unfounded rumor — quickly hardened into a kind of ugly consensus: Poor blacks and looters were murdering innocents and terrorizing whoever crossed their path in the dark, unprotected city.

"As you look back on it, at the time it was being reported, it looked like the city was under siege," said Russel L. Honore, the retired Army lieutenant general who led military relief efforts after the storm.

Today, a clearer picture is emerging, and it is an equally ugly one, including white vigilante violence, police killings, official cover-ups and a suffering population far more brutalized than many were willing to believe. Several police officers and a white civilian accused of racially motivated violence have recently been indicted in various cases, and more incidents are coming to light as the Justice Department has started several investigations into civil rights violations after the storm.

"The environment that was produced by the storm brought out what was dormant in people here — the anger and the contempt they felt against African-Americans in the community," said John Penny, a criminologist at Southern University of New Orleans. "We might not ever know how many people were shot, killed, or whose bodies will never be found."

Broken levees left 80 percent of New Orleans submerged, but in the unflooded area of Algiers Point, for instance, a mostly white enclave in a predominantly black neighborhood on the west bank of the Mississippi River, armed white militias cordoned off many of the streets.

They posted signs that boasted, "We shoot looters." And the sound of gunfire peppered the hot days and nights like thunderclaps of a second storm.

Reginald Bell, a black resident, said in a recent interview that he was threatened at gunpoint by two white men there a few days after the storm. The men, on a balcony a few blocks from his home, yelled at him, "We don’t want your kind around here!"

Then one of the men racked his pump-action shotgun, aimed it at Bell and dared him to be seen again on the streets of Algiers Point, Bell said. The next day, he said, the men confronted him on his porch while he sat with his girlfriend. They shoved guns — a shotgun and a long-nose .357 Magnum — in the couple’s faces and reiterated their demand.

"There was no electricity, no police, no nothing," said Bell, 41, sitting on his porch on a recent afternoon. "We were like sitting ducks. I slept with a butcher knife and a hatchet under my pillow."

The West Bank area of the city was spared any flooding, but in the days and weeks after the storm, it was littered with fallen trees and, according to witnesses, with the bodies of several black men — none of whom appeared to have drowned.

"I done seen bodies lay in the streets for weeks," said Malik Rahim, who lives around the corner from Bell and came to his aid. "I’m not talking about the flooded Ninth Ward, I’m talking about dry Algiers. I watched them become bloated and torn apart by dogs. And they all had bullet wounds.

"We’ve been screaming it from the top of our lungs since those first days, but nobody wanted to listen."

Bell said that he went to the police not long after the confrontation with the two gun-wielding white men but no report or action was taken. It was not until last year when he was interviewed by a federal grand jury looking into civil rights violations in post-Katrina New Orleans that people seemed to pay attention, he said.

Some of the most serious allegations surfaced after investigations by The Times-Picayune and the nonprofit news organization ProPublica, which spotlighted much of the police violence and racially motivated violence around Algiers Point.

One case is that of a former Algiers resident, Ronald J. Bourgeois Jr., who is white and was accused of being part of one of the vigilante groups. He was recently indicted by the federal government on civil rights charges in the shooting of three black men who were trying to leave the city. According to the indictment, Bourgeois, who now lives in Mississippi, warned one neighbor that "anything coming up this street darker than a brown paper bag is getting shot."

The highest-profile case involving the police is the Danziger Bridge shooting in eastern New Orleans, where six days after Katrina, a group of police officers wielding assault rifles and automatic weapons fired on a group of unarmed civilians, wounding a family of four and killing two, including a teenager and a mentally disabled man. The man, Ronald Madison, 40, was shot in the back with a shotgun and then stomped and kicked as he lay dying, according to court papers.

Mayor Mitch Landrieu in May invited the Justice Department to conduct a full review of the city’s Police Department. The Justice Department has also begun several civil and criminal investigations into post-Katrina violence involving the police and civilians.

Thomas Perez, an assistant attorney general, said the federal government was investigating eight criminal cases involving allegations of police misconduct. Many people in the city — including activists, victims and witnesses — had long contended that racial violence was being ignored by local law enforcement.

"We were dismissed as kooks for the last four years," said Jacques Morial, a co-director of the Louisiana Justice Institute, a nonprofit advocacy organization, and the son of New Orleans’ first black mayor. "I think what we are seeing now recalibrates the reality of Katrina, and I think it vindicates lots of folks."

The city’s police superintendent, Ronal Serpas, who took over the department in May, said he was troubled by what has come to light since the storm.

"We have to confront this and look at it head on," Serpas said. "There have been far too many examples of men who have worn this badge and admitted in court to behavior that is an absolute insult to this city and to the men and women of this department who wear this badge with dignity and pride."

On a recent afternoon, Rahim, 62, walked through the streets of Algiers and pointed out where, block by block, the militias had set up barricades and stood guard. He walked along the levee where the charred remains of Henry Glover were found in the trunk of a burned-out car, precipitating the indictment of three current and two former police officers.

"How can you remove the scars from the eyes of all the children who witnessed these atrocities?" Rahim asked.

Honore said that he had been asking himself questions, too.

"I think, every year there is more time for people to reflect on it," he said. "I came out of Katrina with one perspective on it. And there isn’t a month that goes by that I don’t talk to someone who survived it who gives me a different perspective than I had before."