Gunmen opened fire on dozens of people marching in the parade, injuring 19 people, including two children.
Police officials have revealed that three suspects were seen fleeing the scene after the shooting and that most of the injuries sustained by the victims are non life-threatening.
Stars immediately took to Twitter.com to share their dismay, with dance star Moby declaring, "Another terrible and horrifying gun tragedy. how many more???", while singer Abdul added, "My heart, thought (sic) and prayers go out to everyone in New Orleans. Wishing us All peace in our hearts. We are all connected."
Melissa Joan Hart shared a link to the latest news update adding, "Heartbreaking!!" and Simmons asks his followers to "pray for New Orleans".
Cops are appealing for witnesses to come forward with any information that could lead to arrests.