A shooting attack took place late Thursday morning local time at several army sites in Chattanooga, Tennessee, and at least one police officer was shot.
The shooter remains at large, with much of the area near River Park where the incident has developed blocked off by police.
The US Navy reported that a Navy reserve center on Amnicola Highway in Chattanooga was targeted in a shooting. Likewise another Navy building nearby on Lee Highway was also hit.
Chattanooga Mayor Andy Berke announced, "we've got an officer down," although he did not provide the officer's condition. He added that it was a "very, very terrible situation and we need to go figure out how we can handle it."
On Twitter, Berke wrote: "Horrific incident in our community. We will release details as they are confirmed. Prayers to all those affected."
"There has been several (shootings) at several different locations. It's a fluid situation," said John Harmon, a spokesman for the Tennessee Highway Patrol, according to Reuters.
A witness, Gina Mule, told CNN that from a window in a restaurant she saw a man with "a high-powered rifle" open fire with numerous shots from a silver Mustang car, targeting a building where military recruiting offices are located.
Responding to the attack, Chattanooga State University told students and staff to stay inside because of a "confirmed shooting."
The incident brings to mind the 2009 shooting attack at the Fort Hood army base, when Palestinian American Army Major Nidal Hasan unleashed a deadly shooting rampage, murdering 13 and wounding 32. Hasan admitted to conducted the shooting as an Islamist terror attack.
The same base was shot again in April 2014, with the shooter and three victims killed as well as 14 wounded.