UPDATE: One of the two victims died.
A fire reported shortly after 9 p.m. at 265 E. St., sent two residents to the hospital in bad shape.
Arson investigators and police detectives are currently on scene. The homicide unit was summoned as well, due to the severity of one of the victim's injuries.
One firefighter suffered a non-life-threatening injury.
The Boston Fire Department reports fire was showing on the second floor when firefighters arrived.