THE HAGUE, Netherlands — Passengers at Amsterdam's Schiphol airport are facing long waits after a power outage temporarily knocked out its check-in systems.

The outage that hit parts of Amsterdam in early Sunday prompted authorities to briefly shut roads and a rail link to the airport on the outskirts of the Dutch capital.

The airport says on its website that check-in systems were restored early Sunday, but warned passengers to check the status of their flights for updates. The airport says incoming flights "will be reduced in capacity" from 9-11 a.m. and that several departing flights have been cancelled or delayed.

The Dutch power grid administrator, Tennet, says it is investigating the cause of the outage.