Firefighters on the scene of an explosion and fire on the UC Berkeley campus on September 30, 2013. (CBS) Firefighters on the scene of an explosion and fire on the UC Berkeley campus on September 30, 2013. (CBS)

BERKELEY (KCBS/KPIX 5) — A power outage triggered an explosion and fire at the University of California at Berkeley on Monday evening, prompting an emergency evacuation of the campus and hospitalizing one person with burns, according to authorities.

The widespread power outage on campus was reported just before 5 p.m., causing university officials to cancel evening classes and tell students to suspend lab activity and leave the academic buildings.

Then about two hours later, an explosion and fire occurred in an underground electrical vault near California Hall during efforts to restore power; officials ordered evacuations as smoke shrouded the central campus. The fire was largely extinguished by 8 p.m.

Berkeley acting fire Chief Gil Dong said that one student suffering burns was taken to a hospital by ambulance; a few others suffered minor injuries and were evaluated by emergency personnel on campus.

Fire crews also had to free about 20 people trapped in dormitory elevators on the west side of campus due to the power disruption.

The outage and blast stemmed from a power system failure that may have been caused by a copper wire theft from an underground vault at a campus substation last week, UC Berkeley spokesman Dan Mogulof indicated.

Late Monday night, power remained out for most of the campus – although residential halls had reopened with power provided by backup generators.

UC officials were advising people to stay away from the campus until power could be fully restored and it was unclear whether classes would resume on Wednesday.

There was also a reported ammonia leak in a room at Latimer Hall on Monday evening, but Dong said it was unknown if that event was related to the other incidents.

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