New Orleans

The local sheriff said an "initial shooter" opened fire, striking two people, which prompted several others at the shop to fire their own weapons.

The two people and the initial gunman were killed. They have not been publicly identified.

Officials said investigations into the shooting at the Jefferson Gun Outlet, in a New Orleans suburb, were ongoing.

"From what I understand I have multiple shooters here at this location that were either customers, employees or individuals here at the location itself," Jefferson Parish Sheriff Joseph Lopinto told reporters.

This week, Adams was sensationally traded by the Oklahoma City Thunder after seven years at the NBA club, since making his debut back in 2013 when he was the 12th overall pick in the draft that year.

The two-year extension is reportedly worth US$35 million (NZ$50.16m), according to ESPN.

Adams, 27, had one year remaining on his four-year deal with the Thunder, reportedly worth US$100m (NZ$143.3m).

According to ESPN, Adams will still bank US$27.58m (NZ$39.52) in the upcoming 2020-21 season.

Some of the victims had been accused of murdering a police chief, but were acquitted after a trial.

Angry about the verdict, a mob of racist vigilantes in the city attacked and publicly hanged them.

Mayor LaToya Cantrell is due to apologise for the killing - believed to be the largest recorded lynching in US history - on 12 April.

She will issue the apology at an Italian-American cultural centre in the city, a spokesman told the Associated Press news agency.

What happened in 1891?

He's chosen to deliver remarks at Warren Easton Charter High School, the same school he visited on the first anniversary of the catastrophic storm. He is accompanied by his wife, Laura, whose library foundation helped rebuild what is the oldest public school in New Orleans.

The school's success is one of the president's brighter moments in what was an extremely trying time for the Bush administration. Bush was vilified for his government's lackluster response.

He offered the city as an example of what can happen when people rally to build a better future after extraordinary trials.

The president's first stop on a visit marking the storm's 10th anniversary was Tremé, one of the oldest black neighborhoods in America and an area that experienced significant flooding during Katrina. A cheering crowd welcomed him to a place where homes inundated by the storm have been rebuilt.