Aug 3, 2012 8:52 AM by Kate Richards
ERIE, Colo. (AP) - Federal investigators are trying to determine the cause of an explosion at Erie Middle School that injured three workers.
The Occupational Safety and Health Administration is looking into reports the explosion happened when a plumbing contractor was lighting a hot water heater.
According to the Boulder Daily Camera, one of the victims remains in critical condition, one is in serious condition and one was treated and released from a hospital. They have not been identified. No students or teachers were in the building at the time of the explosion.