BATON ROUGE - Firefighters, police officers and paramedics responded to River Road across from Farr Park on Thursday afternoon. 

Sources at the scene said first responders got a mayday call from the Coast Guard concerning someone on the Mississippi River. A rescue helicopter was launched to the area, the Coast Guard confirmed.

As of 5:50 p.m., no one has been located. The Coast Guard is working with the East Baton Rouge Sheriff's Office to locate where the call originated.

This is a developing story.