The two Amtrak engineers involved in the Dec. 12 train crash in Boston have been suspended without pay pending an investigation, and a signal near the crash site has been changed.

An "all clear" track signal near Boston's Back Bay Station has been changed to require inbound trains to brake to 30 mph, Amtrak spokeswoman Sue Martin said.Amtrak said in a statement that engineer trainee Richard Abramson 41, of Trumbull, Conn., and chief engineer Willis Copeland, 53, of Bethany, Conn., would be "removed from engine service."