Police are looking for two suspects who opened fire in New Orleans, killing three people and injuring seven more, city police spokesman Aaron Looney said.
Harrison spoke with family members and friends at the scene of the "volatile and tense situation".
The shooting left a trail of injured and dead as well as a trail of tears as family members and friends shrieked and screamed with grief and pain at the latest carnage on New Orleans streets.
A man at the scene told reporters, "It's not normally like this right here".
Three of the seven injured people were taken by ambulance to University Medical Center's trauma center, police said.
"This was a large crowd and we know that people saw something, heard something", Harrison said.
The local NBC affiliate said that one of the victims believed to be in critical condition underwent surgery. "We need them to know that they can trust us and come to us". NOLA.com/The Times-Picayune reported two men were trying to console two sobbing women as one of the women shouted: "That's my baby".
Police said the four remaining victims were transported in private vehicles.
Police asked the community to share any information they may have about the shooting.
The earliest case of violence in the block of South Claiborne Avenue is one of the most storied killings in New Orleans history.
"I speak for everyone in our city when I say we are disgusted and infuriated, and we have had more than enough", she wrote.
"There is no place in New Orleans for this kind of violence". Three more lives - gone.