BOSTON (AP) - Authorities say a charter bus full of passengers has struck a bridge in Boston, injuring several people.   The bus carrying 42 people was coming from Harvard University and was heading back to Pennsylvania when it struck an overpass in the Allston neighborhood shortly before 8 p.m., according to the Boston Fire Department.  

Massachusetts State Police say several people aboard the bus were injured, though it has no immediate details on the nature of the injuries.   State Police say the Calvary Coach Bus out of Philadelphia was too high for the roadway. A spokesman for the bus company says he has no immediate information on the crash.  

Photos posted on the Fire Department's website showed firefighters extracting people from the bus.  The accident happened on Soldiers Field Road, a major crosstown roadway in Boston that curves along the Charles River and passes by Harvard and Boston University. It is a major roadway to the Massachusetts Turnpike