The pair were on the tracks at the Diedorf station near Augsburg when a train pulled in at speed and the driver was unable to stop in time to avoid hitting them.
Mystery surrounds the identity of the pair - and their relationship to each other, a police spokesman said on Wednesday. A forensic examination was expected to offer some answers on Thursday.
The IC train travelling between Munich and Karlsruhe hit the pair despite the driver slamming on the emergency brake - he was only able to bring the train to a halt around 500 metres down the tracks.
The track between Augsburg and Ulm was shut for several hours.