Several police officers shot while on duty in Baton Rouge

At seven officers were injured, and three are feared dead, reports CNN, citing a source with knowledge of the investigation.

While Baton Rouge Police Sgt. Don Coppola did not know the extent of the injuries or give the precise number of officers injured, he says they were rushed to a local hospital.

The shooting happened early Sunday, less than 1 mile from police headquarters.

Coppola said that authorities believe the "scene is contained," meaning that a shooter was unlikely on the loose.

Mayor-president of East Baton Rouge Parish Kip Holden told CNN the scene is still "active," although the shooter is believed to be down. A state police spokesman confirmed to NBC that the gunman was shot but his condition remains unclear.

Photojournalist for Lousiana news source The Advocate Hillary Scheinuk tweeted that police are consistenly arriving on the scene, as well as the coroners office. 

Police-community relations in Baton Rouge have been especially tense since the killing of 37-year-old Alton Sterling, a black man killed by white officers earlier this month after a scuffle at a convenience store. The killing was captured on cellphone video and circulated widely on the internet.