The Louisville Metropolitan Police Department says there are "multiple casualties" in the Kentucky city Monday as officers are responding to "reports of an active aggressor."
"We are confirming reports of an active aggressor in the 300 block of East Main. Please stay out of the area," police said in tweet. "There are multiple casualties."
Images taken in the area showed an officer with his weapon drawn.
Agents from the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) also were photographed at the scene.
The FBI's Louisville office also tweeted that its "special agents have responded to the scene of this morning's shooting in downtown Louisville and are assisting our law enforcement partners."
Louisville Mayor Craig Greenberg also said there was an "active police situation downtown" and for the public to "please avoid the area around Slugger Field until further notice."
Further details about the incident were not immediately available.
This is a developing story. Please check back for updates.
