Police in the UK are investigating the cause of a collision between two passenger trains in central England, near Bedford, late Friday. The crash kills the driver of one of the locomotives, police say. On Saturday, officials report that nine people remain in critical condition. Other injured passengers are also treated in hospitals: one report says more than 80 people receive hospital care following the accident, while another notes that dozens of passengers were still being treated later. A witness quoted by the BBC describes the trains stopping before being struck from behind. The reports indicate the trains were travelling toward London and that the incident occurs on a stretch of track north of the capital. Coverage also notes continued emergency response and hospital treatment in the days following the collision as investigators work to determine what led to the crash.