our correspondent steven carroll has the latest from the scene. >> the operations to remove the carriages and the train lines here will continue through saturday night and all day sunday, the most difficult part of it, we're told would be removing this carriage which lies on its side on the rail lines. the c.e.o. had told us that their initial investigations had shown the cause to be a faulty rail switching mechanism that removes trains from one rail line to another. they are conducting a check across all of its record, 5,000 different records. an inquiry went into what caused the accident which resulted in six deaths that of four men and two women and has left several more in a serious condition in the hospital. >> will a french national rail has accepted responsibility for that accident. as we just heard there they're promising to carry out immediate checks on all railway tracks right across france. he believes that a lack of resources may have been a factor. our correspondent explains. >> at 5:14 the train was heading south from central paris traveling within the speed limit . the swit