The accident occurred when the Metro Blue Line train was traveling south on San Pedro Street at Washington Boulevard. Brian Humphrey, a spokesman for the Los Angeles Fire Department told the LA Times that officers were still investigating the cause of the accident but confirmed that the train did not derail.
NBC News reports that medical personnel were attending to at least 40 people who were on board the bus and eight people who were traveling on the train.
LA's metro Blue Line has been the subject of widespread criticism over safety concerns since it opened as the county's first light-rail line in 1990. The LA Times reports that 2012 is shaping up to be the deadliest in the train line's history with 22 accidents and six fatalities already this year.
In 1999, the Blue Line became California's deadliest rail transit route with 50 accidents killing 10 people and injuring 40 others. Most of the accidents, like Monday's bus collision, involved motor vehicles at street crossings.