UPDATE: 12:40 a.m. EST -- Two groups opened fire on each other at a New Orleans playground where hundreds of people had gathered to shoot a music video Sunday night, the Associated Press reported, citing police. Earlier, witnesses claimed that at least two gunmen shot several people at Bunny Friend Park, injuring 16.

Authorities reportedly said that those injured are currently in stable condition. An investigation is reportedly underway into the incident. While a video was being filmed at the park, the event was primarily a block party, police spokesman Tyler Gamble reportedly said, adding that neither event had a permit to use the park.

Original story:

Several people have been hospitalized after at least two gunmen opened fire on a crowded playground in New Orleans on Sunday night, local media reports said, citing police and witnesses. At least 16 people were reportedly injured in the incident.

Officers said that over 500 people were present at the Bunny Friend playground in the city's Upper Ninth Ward to shoot a music video. Authorities told WGNO, an ABC-affiliated television station, that the video was being shot without a permit to use the park.

At least 10 of the victims were taken to University Medical Center in New Orleans, local television station WWL reported, citing police. The other victims were taken to hospital by private vehicles. 

It was unclear how serious the wounds were, or what started the shooting, but some reports said the gunmen fired into the crowd after an argument. An investigation is underway.

Mayor Mitch Landrieu and New Orleans Police Department Chief Michael Harrison, who were present at the scene of the shooting, reportedly urged witnesses to come forward and help locate the suspects.

Some witnesses told the Times-Picayune newspaper that they saw a man with a machine gun head toward Louisa Avenue, north of the park, after the shootings.