Firefighters responded at about 4:55 a.m. to reports of smoke in Ehrman Hall, a University of California at Berkeley dorm located near campus at 2650 Haste St., Battalion Chief Bill Kehoe said.
More than 100 students in the building had to be evacuated and two were hospitalized for minor smoke inhalation, Kehoe said. The victims are expected to survive.
Firefighters arriving to the building found heavy smoke on the fourth through eighth floors of the eight-story building, as well as lighter smoke on the lower levels, he said.
The blaze is believed to have started from "something discarded in the trash chute that ignited debris at the bottom" of the building, Kehoe said.
Smoke traveled through the chute to the various floors of the building before firefighters were able to get to the basement to extinguish the fire at about 5:30 a.m., according to Kehoe.
He said he "was surprised at the minimal amount of trash in there for the amount of smoke that was generated," adding that "every fire has a distinct smell, and trash fires definitely have their own smell."
UC Berkeley officials were working as of 10 a.m. to get most of the students back into their rooms soon, but Kehoe said some rooms may not be habitable for a while, some due to smoke damage and others because firefighters had to force entry into them.
Campus authorities "have opened the dining commons to give them a place to hang out in the meantime," he said.
A damage estimate for the blaze has not been determined, he said.
Because Ehrman Hall is a university-owned building, James Feld, the campus' senior deputy fire marshal, will be heading the investigation into what exactly sparked the fire, according to Kehoe.