Denmark has suspended all rail links with Germany after police stopped hundreds of migrants at the border.
Danish police also closed a motorway between the two countries when some asylum seekers began walking north after being forced off a train.
They say their destination is Sweden.
As the EU struggles with a major migrant crisis, the European Commission has proposed that 120,000 additional asylum seekers should be shared out between members, using binding quotas.
Denmark’s DSB rail operator said trains to and from Germany had been suspended for an indefinite period because of exceptional passport checks.