BERLIN (AP) — Scheduled maintenance on a communications system triggered an outage on Germany's railway that brought all trains to a halt, stranding travelers across the country, the network operator said Wednesday as it faced criticism and questions over the embarrassing chaos.

The main railway operator, federal government-owned Deutsche Bahn, apologized for the abrupt halt in services late Tuesday, when all trains in Germany ground to a halt. Service resumed gradually about two hours later, after midnight.

The Associated Press