Image caption Defence lawyers say officers did the best they could in the chaos after the storm

A US federal jury has convicted five police officers in New Orleans over fatal shootings in the chaotic aftermath of Hurricane Katrina.

Two unarmed residents were killed and four others wounded in the incident on the Danziger Bridge after the 2005 storm.

But the jury decided that neither of the fatal shootings was a murder.

The five officers were convicted of violations stemming from the cover-up of the deaths.

Four of the men were also found guilty of civil rights violations.

Former officers Robert Faulcon, Anthony Villavaso, Sgt Robert Gisevius and Sgt Kenneth Bowen were convicted of taking part in the shootings that killed James Brissette, 17, and Ronald Madison, 40, as well as the alleged cover-up.

Retired officer Sgt Arthur Kaufman, who investigated the shootings, was charged only in the alleged cover-up.

Most of New Orleans was flooded by the hurricane and there was widespread looting and violence in the storm's aftermath.

'Falsify reports'

It was unreasonable for these officers to fire even one shot, let alone dozens Theodore Carter, Assistant US Attorney

During the five-week trial, prosecutors said that police shot six unarmed people on the Danziger Bridge on the morning of 4 September 2005, less than one week after the storm struck New Orleans.

The US justice department said that the evidence at the trial had established that three officers opened fire on an unarmed family on the east side of the bridge, killing a 17-year-old boy and wounding four other members of the family.

Minutes later, according to testimony, a second shooting occurred on the west side of the bridge, where officers shot at two brothers - Lance and Ronald Madison. Forty-year-old Ronald, who had severe mental disabilities, was shot dead as he tried to run away.

In closing testimony on Tuesday, Assistant US Attorney Theodore Carter said police had no justification for shooting unarmed people attempting to cross the Danziger in search of food days after Katrina struck.

"It was unreasonable for these officers to fire even one shot, let alone dozens," he had said.

'Healing power'

Lawyers representing the officers argued the police were shot at before they returned fire and believed their lives were in danger.

But, according to the US justice department, Kaufman and the other officers tried to make the shootings appear justified by creating a cover-up.

Kaufman claimed to have found a gun - which he had actually taken from his own home - on the bridge the day after the shooting. He also invented fictional witnesses and witness statements to justify the officer's actions. He faces a maximum sentence of 120 years in prison.

Since Katrina, the New Orleans police department has been the target of allegations of corruption and brutality.

"This was a critical verdict. I cannot overstate the importance of this verdict," US Attorney Jim Letten said.

"The power, the message it sends to the community, the healing power it has," he added.

Last year, New Orleans Mayor Mitch Landrieu described the city's police department as "one of the worst" in the country, and asked the US government to aid reform efforts.

The officers will be sentenced in mid-December. Some face potential multiple life sentences.