German airports say heavy snowfall overnight has grounded more than 200 flights and caused major delays, and the country’s highways are clogged with traffic.

Frankfurt airport spokesman Timo Ross said on Friday 160 flights have been cancelled so far, and the number is expected to rise throughout the day.

Mr. Ross said the airport, continental Europe’s second-biggest hub, had to be closed for about an hour late Thursday, and an estimated 1,000 passengers were stranded overnight.

Munich airport, Germany’s second-largest hub, reported 86 cancellations and major delays.

Roads were clogged by snow, and in North-Rhine Westphalia state alone authorities reported traffic jams of more than 185 kilometers (115 miles) on highways, and 251 weather-related accidents that left 19 people injured.

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