Argentina''s president declared a two-day period of mourning after a commuter train plowed into a barrier at a Buenos Aires station Wednesday, killing 49 people and injuring hundreds more, according to the (CNN). "The government and people of Argentina give their solidarity and weigh the pain felt by the families of the victims," President Cristina Fernandez de Kirchner said in a statement declaring the mourning period. The crash injured 675 people, and more than 460 were hospitalized. "Never in my life had I seen anything like this," Transportation Secretary Juan Pablo Schiavi said. Authorities will use GPS data, security camera footage, audio recordings from the driver''s cabin and maintenance records in their investigation, Schiavi said.