NEW ORLEANS -- New Orleans firefighters are investigating a four-alarm fire at the home of former Mayor Dutch Morial. The fire started shortly before 5 a.m. Friday. No one was home at the time. Family members told WDSU the home was under renovation so Morial's wife, Sybil, could move back in. Two firefighters were treated for heat exhaustion at the scene, but their injuries are not serious. Investigators do not know how it started.