BERLIN -- German prosecutors Tuesday said they are investigating three railway workers for negligent homicide in relation to a train accident last week that left five people dead and many more injured.

The double-deck regional train that derailed Friday near the southern Bavarian town of Garmisch-Partenkirchen had about 140 people on board, including students headed home from school for the Whitsun holiday.

According to Germany's dpa news agency, a 14-year-old boy was killed along with four other women. Two of these were refugees from Ukraine. More than 40 people sustained injuries.

Prosecutors refused to give details about the investigation, including reasons for negligence by rail workers.