President Vladimir Putin sent his condolences to King Juan Carlos I of Spain over the train derailment that claimed the lives of at least 78 people Thursday.
The accident occurred in northwestern Spain near the city of Santiago de Compostela.
The train was traveling from Madrid to Ferrol with 218 passengers aboard when it derailed on Wednesday at about 8:30 p.m. local time while approaching a curve at a high speed. All the train's eight carriages came off the tracks.
Spanish authorities have begun an investigation into the causes of the crash. Putin said Russia "shared in grieving" with the friendly nation of Spain.