German train drivers have gone on a one-day strike, disrupting services and bringing delays for commuters.
Officials say a prolonged dispute would hurt the economy
Negotiations collapsed after train operator Deutsche Bahn's (DB) failure to improve its wage offer, the GDL union said.
The union says its train drivers are underpaid compared with counterparts elsewhere in Europe.
DB said about half of regional services were cancelled, but that long-distance rail services are "stable".
Wage rise row
The GDL union, representing some 34,000 drivers, began walkouts on regional services at 0001 GMT on Friday.
It is holding out for salary increases of up to 30%.
DB has already agreed a smaller deal with two other unions which will see workers receive a 4.5% rise in wages.
Government officials have warned that a prolonged strike could damage the German economy.
Deutsche Bahn carries some 5 million passengers daily.